Halal Slaughter of Livestock: Animal Welfare Science, History and Politics of Religious Slaughter (Animal Welfare, 22) 3031175654, 9783031175657

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Animal Welfare

Awal Fuseini

Halal Slaughter of Livestock: Animal Welfare Science, History and Politics of Religious Slaughter

Animal Welfare Volume 22

Series Editor Clive Phillips , Estonian University of Life Sciences and Curtin University, Perth, WA, Australia Advisory Editors Marieke Cassia Gartner, Atlanta, GA, USA Moira Harris, Shrewsbury, Shropshire, UK Stephanie Torrey, Guelph, ON, Canada

The Animal Welfare series has been designed to help contribute towards a culture of respect for animals and their welfare by producing academic texts addressing how best to provide for the welfare of the animal species that are managed and cared for by humans. Books in the series do not provide a detailed blue-print for the management of each species, but they do describe and discuss the major welfare concerns, often in relation to the wild progenitors of the managed animals. Welfare has been considered in relation to animals’ needs, concentrating on nutrition, behaviour, reproduction and the physical and social environment. Economic effects of animal welfare provision were also considered where relevant, as were key areas where further research is required.

Awal Fuseini

Halal Slaughter of Livestock: Animal Welfare Science, History and Politics of Religious Slaughter

Co-ordinating Editor: Moira Harris

Awal Fuseini Huddersfield Business School Huddersfield, UK Agriculture and Horticulture Development Board Kenilworth, UK

ISSN 1572-7408 Animal Welfare ISBN 978-3-031-17565-7 ISBN 978-3-031-17566-4 https://doi.org/10.1007/978-3-031-17566-4

(eBook)

# The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 This work is subject to copyright. All rights are solely and exclusively licensed by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Dedicated to Saha, Suglo, Simli and Lulah-Fatima

Foreword

The Halal industry has been on an upward trajectory for many years. The global Muslim population has grown from 1.6 billion in 2010 to 1.9 billion in 2020. Likewise, their share of the world population has increased from 23.4% to 24.7%. Not only is this population relatively younger, but it is also richer as the middle-class grows around the world. A young, rich and growing market is a food producer’s dream. The rising prevalence of Halal has led to an increased need to understand its core principles and the changes required to take advantage of the opportunity. Observers of the Halal industry quickly discover that Islam places a high status on animal welfare. However, poor practices and misinformation lead to tensions in the marketplace arising primarily due to a lack of application and understanding. Dr Awal Fuseini, a highly sought-after expert on Halal, has already detailed the opportunities and religious framework in his 2020 publication ‘Halal Meat Production and Market Opportunities: A 21st Century guide to the Halal market’. This new book specifically goes deeper into Halal slaughter, with a deep dive into its scientific, religious and socio-economic aspects. The seriousness of animal welfare is emphasised with detailed chapters on consciousness, unconsciousness and death, alongside practices that make the process better or worse for both the animal and the consumer. Socio-economic aspects, including anti-Halal political movements and wider ethical considerations in meat production, are discussed in refreshing detail. I applaud his latest book and urge every stakeholder and food student to study it earnestly and help manifest the true ideals of Halal in the marketplace. It is a riveting read for all involved in the sector. Euro Quality Lambs UK January 2022

Rizvan Khalid

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Animal Welfare Series Preface

Animal welfare is attracting increasing interest worldwide, and the knowledge and resources are available to, at least potentially, provide better management systems for farm animals, as well as companion, zoo, laboratory and performance animals. The key requirements for adequate food, water, a suitable environment, companionship and health are important for animals kept for all of these purposes. The attention given to animal welfare in recent years derives largely from the fact that the relentless pursuit of financial reward and efficiency, to satisfy market demands, has led to the development of intensive animal management systems that challenge the conscience of many consumers, particularly in the farm and laboratory animal sectors. Livestock are the world’s biggest land users, and the farmed animal population is increasing rapidly to meet the needs of an expanding human population. This results in a tendency to allocate fewer resources to each animal and to value individual animals less than the group. In these circumstances, the importance of each individual’s welfare is diminished. Increased attention to welfare issues is just as evident for zoo, companion, sport and wild animals. Of growing importance is the ethical management of breeding programmes since genetic manipulation is now technically advanced. There is less public tolerance of the breeding of extreme animals if it comes at the expense of animal welfare (e.g. brachycephalic dogs). The quest for producing novel genotypes has fascinated breeders for centuries. Dog and cat breeders have produced a variety of deformities that have adverse effects on their welfare, but nowadays the breeders are just as active in the laboratory, where the mouse is genetically manipulated with equally profound effects. In developing countries, human survival is still a daily uncertainty for many, so that provision for animal welfare has to be balanced against human welfare. Animal welfare is usually a priority only if it supports the output of the animal, be it food, work, clothing, sport or companionship. However, in many situations, the welfare of animals is synonymous with the welfare of the humans that look after them, because happy, healthy animals will be able to assist humans best in their struggle for survival. In principle, the welfare needs of both humans and animals can be provided for, in both developing and developed countries, if resources are properly husbanded. In reality, the inequitable division of the world’s riches creates physical and psychological poverty for humans and animals alike in many parts of the world. ix

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Animal Welfare Series Preface

The intimate connection between animals and humans that was once so essential for good animal welfare is rare nowadays, having been superseded by technologically efficient production systems where animals on farms and in laboratories are tended by increasingly few humans in the drive to enhance labour efficiency. With today’s busy lifestyles, companion animals too may suffer from reduced contact with humans, although their value in providing companionship, particularly for certain groups such as the elderly, is beginning to be recognised. Animal consumers also rarely have any contact with the animals that are kept for their benefit. In this estranged, efficient world, people struggle to find the moral imperatives to determine the level of welfare that they should afford to animals within their charge. A few people, and in particular many companion animal owners, strive for what they believe to be the highest levels of welfare provision, while others, deliberately or through ignorance, keep animals in impoverished conditions in which their health and wellbeing can be extremely poor. Today’s multiple moral codes for animal care and use are derived from a broad range of cultural influences, including media reports of animal abuse, guidelines on ethical consumption and campaigning and lobbying groups. This series has been designed to contribute towards a culture of respect for animals and their welfare by producing learned treatises about the provision for the welfare of the animal species that are managed and cared for by humans. The early species-focused books were not detailed management blue-prints; rather they described and considered the major welfare concerns, often with reference to the behaviour of the wild progenitors of the managed animals. Welfare was specifically focused on animals’ needs, concentrating on nutrition, behaviour, reproduction and the physical and social environment. Economic effects of animal welfare provision were also considered where relevant, as were key areas where further research is required. This volume again departs from consideration of a single vertebrate species model to a more universal process, the slaughter of livestock animals, and examines this primarily from the perspective of Halal (slaughter in accordance with the traditions and requirements of the Islamic faith). Awal Fuseini first details the science of conscious perception, describing the nervous system and explaining concepts such as pain, consciousness, unconsciousness and death. He then goes on to describe the ways in which cattle, sheep and poultry are handled and restrained prior to slaughter as well as the various commercially available methods of slaughter and pre-slaughter stunning. The history of stunning, starting with archaic and unreliable methods and progressing to those in use today, is traced, as well as the requirements of slaughter without stunning, as practised by some faith groups and during conventional (non-faith) slaughter in many parts of the developing world. Awal then describes the development of Halal slaughter, starting with its origins in pre-Islamic and Islamic Arabia and explaining, with the help of passages from the Quran, the various nuances and interpretations of what is required, acceptable and forbidden. Both Muslim and non-Muslim readers will learn much from this volume about dietary and slaughter rules for those of the Muslim faith, almost a quarter of the

Animal Welfare Series Preface

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world’s population. In the final chapter, socio-political aspects of Halal slaughter are considered. The Boycott Halal Movement and non-stun slaughter movement are explored, and it is suggested that some of the objections to Halal slaughter (as opposed to non-stun slaughter) derive from a growing anti-Muslim sentiment. The global Halal food market, catering to a growing Muslim population, is expanding exponentially and (as with conventional production) there are ethical challenges involved with Halal meat production. Dr Fuseini emphasises the need for animal welfare to play a bigger part in Halal certification and audits. He also calls for increased dialogue and discussion between stakeholders (such as politicians, scientists, religious scholars, animal welfare organisations and those involved in religious slaughter and the Halal food chain) to promote understanding and consensus, ultimately improving the welfare of the many millions of animals involved. Shropshire, UK WA, Australia

Moira Harris Clive Phillips

Preface

Humans have utilised animals for food and other benefits for millennia. There is, however, a growing vocal minority who are of the view that animals should not be slaughtered for food or any other benefit. Nonetheless, the majority of the global population are meat eaters, probably due to the important role animal protein plays in safeguarding human health. Meat also features in cultural and religious festivals around the globe. As a result of improvement in our understanding of animal behaviour, neurophysiology, anatomy and animal welfare, it has been demonstrated through scientific research that the pain and distress associated with pre-slaughter handling and slaughter (neck cutting) can be mitigated with a number of scientifically validated procedures. Furthermore, to assure the protection of the welfare of non-human animals during slaughter, there are legislative instruments in most industrialised economies, e.g., the EU, USA and others, specifying the design of transport vehicles, transit times, stocking densities, lairaging, pre-slaughter restraint, stunning and/or bleeding and post neck cut management, all aimed at mitigating the pain and distress associated with the series of events leading to the death of animals. I decided to write this book for three reasons: first, to highlight the economic significance of the Halal market, secondly, to suggest ways of improving animal welfare during handling and slaughter and, last but not the least, to discuss the sociopolitical aspects of Halal meat production. The book is based on my years of experience working in the meat industry in the UK and my research experience, which led to the publication of my first book on Halal meat production and several scientific papers in some high impact peer-reviewed journals. I grew up in Ghana where for a long time I kept a small number of animals, and developed a keen interest in their welfare, which ultimately contributed to me following an academic route in agriculture and meat science. On completion of a degree in agriculture from Cape Coast University, I topped it up with an M.Sc. in Meat Science and Technology from Bristol University. It was during my M.Sc. course that I developed a particular interest in understanding how the pain associated with neck cutting could be mitigated. Thankfully, I was awarded a Ph.D. studentship by the Humane Slaughter Association (HSA) to investigate the development and commercialisation of a novel method of head-only electrical stunning of cattle.

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Preface

To summarise, my Ph.D. research led to the development of a prototype electrical stunning system which is currently undergoing refinement for possible commercialisation. It is likely that the new technique may appeal to some religious communities because it is a non-lethal method of stunning. It has been scientifically demonstrated that, when performed correctly, stunning can induce brain dysfunction and loss of consciousness. It is against this background that the European Council Regulation, EC 1099/2009 requires the stunning of animals prior to slaughter, with the exception of animals slaughtered for consumption by people of faith. I previously worked in Halal certification with the UK’s Halal Food Authority (HFA) and I am well aware that, at present, the majority of animals slaughtered during Halal meat production are stunned prior to slaughter. Among other objectives, this book aims to highlight ways in which the welfare of animals can be improved during religious slaughter. Huddersfield, UK

Awal Fuseini

Aims and Objectives of the Book

In recent years, there has been a rise in the number of people switching from meatbased diets to vegetarian or vegan diets. On the website of the UK’s Vegan Society, the organisation reported that the number of vegans in the UK quadrupled between 2014 and 2019 to 600,000 (1.16% of the population) (The Vegan Society, 2019). A number of reasons have been attributed to the switch from animal protein to plantbased diets. However, consumer health, environmental sustainability and concern for animal welfare are the three main reasons. Whilst the author of this book recognises the fact that some consumers have avoided the consumption of meat on the grounds of environmental sustainability and health, these two areas are not the focus of this book. The book explains the science of conscious perception with regard to the slaughter of animals, with emphasis on mitigations to improve animal welfare during handling and slaughter. Furthermore, the book examines the rise in the activities of animal welfare activists and groups who are calling for a ban or boycott of Halal food. The book looks at campaigns against Halal from two angles, those calling for a ban on Halal slaughter without stunning and those campaigning for a boycott of Halal certified products. In the UK, for instance, and until recently, political movements such as Britain First have launched sustained attacks on Halal meat processors and certification bodies, accusing the Halal sector of funding terrorism, a claim that cannot be substantiated. This has led to legal challenges, with the recent case being between Britain First and a major UK certifier, and similar legal challenges have been reported in Australia. The author has many years of experience working in the Halal sector in the UK, and his view is that there is no evidence to suggest that any profits from the sale of Halal meat or revenue generated from Halal certification is used to fund terrorist activities. This book sets out to address some of these unsubstantiated claims. The author is also aware that some Halal certifiers and meat processors donate large sums of money to Muslim and non-Muslim charities around the world; unfortunately, these good causes rarely feature in mainstream media reportage. On the welfare aspects of slaughter, the rise in animal welfare activism has led to an increased number of covert recordings in abattoirs, carried out to highlight animal welfare compromises in both Halal and conventional operations. What is interesting is that these covert recordings rarely highlight good slaughter practices. This has led xv

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Aims and Objectives of the Book

to some critics suggesting that the ultimate motive of the activists is to present a bad image of the meat industry, with a view to discouraging people from consuming meat, without necessarily presenting a true picture of what actually happens in abattoirs. This book aims to present the facts surrounding the welfare aspects of both conventional and religious slaughter and suggest measures that can be adopted during pre-slaughter handling and neck cutting to mitigate the pain and distress associated with slaughter.

Target Readership The author hopes to reach as many readers as possible, including meat eaters and non-meat eaters. Whilst some of the information presented are very technical, the author has attempted to express this in a form that can easily be understood by the general reader. The main target readers of the book are the following: • • • • • • • •

Veterinarians and meat scientists Animal science, welfare and veterinary students Technical managers, meat processors and abattoir operators Competent authority and policy makers Farmers and agricultural workers Meat and non-meat consumers Halal Certification Bodies and Halal Accreditation Authorities Animal Welfare Officers (AWO) and Poultry Welfare Officers (PWO)

Outline of the Book Chapter 1 gives a general introduction to the debate surrounding the consumption and avoidance of meat. Chapter 2 considers the science of conscious perception and death, with emphasis on neural communication, consciousness, unconsciousness, death and the assessment of unconsciousness during stunning and slaughter. Chapter 3 looks at transport of poultry and pre-slaughter handling of the major Halal species, with emphasis on the impact of good handling, restraint and slaughter on animal welfare and the quality of meat. Chapter 4 examines religious slaughter with a focus on Halal slaughter. The nuances and historical aspects of Halal slaughter, stun and non-stun slaughter are discussed in greater detail. Chapter 5 discusses the economic and ethical significance of Halal meat production with emphasis on the value of the Halal market. The author also discusses the recent rise in campaigns against Halal food production and certification as well as calls for a ban on slaughter without stunning.

Acknowledgements

A number of people have supported me in various ways through my education and career which has directly or indirectly led to the publication of this book. I would like to express my sincere gratitude to the following people for supporting me during my Ph.D. research at Bristol University: Prof Toby Knowles, Dr Andrew Grist and Mr Steve Wotton MBE. I would also like to thank Dr Phil Hadley of the Agriculture and Horticulture Development Board (AHDB) for his guidance and unconditional support over the years. I would like to thank Mr Rizvan Khalid, Managing Director of Euro Quality Lambs, a UK-based Halal lamb processor, who agreed to be interviewed and for the information to be included in Chap. 5; he also kindly penned the foreword. I thank Miss Lesley Moffat, founder of Dutch-based animal welfare charity, Eyes on Animals, who agreed to be interviewed to give an insight into the operation of her organisation and the part they play in promoting animal welfare during conventional and Halal slaughter in a number of countries. I am also indebted to my dear mother, Hajia Fatima, who worked tirelessly to ensure that I received the right education since the death of my dad in 1981, when I was just a year old. Mum, your efforts have not been and will never be in vain. To my lovely wife and biggest fan, Hamna, I would like to acknowledge your patience, encouragement and support over the last decade. My children, Saha, Suglo, Simli and Lulah-Fatima are also worthy of a mention for keeping me on my toes. They kept reminding me of the deadline for submitting the manuscript and Saha assisted in editing some of the photos in the book.

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Disclaimer

Every effort has been made in good faith to ensure that the information contained in this book is true, correct, complete and appropriate at the time of writing. Nonetheless, the author and publisher do not accept responsibility for any omission or error, for any injury, damage, loss or financial consequences resulting from the use of this book. The views and opinions expressed in this book are those of the author and do not necessarily reflect the views and position of any institution or organisation where the author is, or has been, employed. The content is the result of many years of experience by the author, gained while working in the meat industry in various capacities. It also draws on the author’s research experience, which has resulted in the publication of numerous scientific papers and his first book on animal welfare, slaughter and consumer behaviour in various peer-reviewed scientific journals. Expert contributions and information obtained from other sources are duly acknowledged.

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Contents

1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 6

2

The Science of Conscious Perception and Death . . . . . . . . . . . . . . . . 2.1 Neural Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.1 Neurons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1.2 Synaptic Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Consciousness, Unconsciousness and Death . . . . . . . . . . . . . . . . . 2.2.1 Consciousness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.2 Unconsciousness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.3 Death . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2.4 Assessment of Unconsciousness . . . . . . . . . . . . . . . . . . . 2.2.5 Assessment of Death . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3 Stunning of Animals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3.1 Commercially Available Stunning Methods . . . . . . . . . . . 2.4 Pain Perception in the Unconscious State . . . . . . . . . . . . . . . . . . . 2.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 11 11 12 15 15 17 18 20 29 31 31 41 41 42

3

Pre-slaughter Handling and Possible Impact on Animal Welfare and Meat Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Poultry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.1 Transport of Poultry . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2.2 Removal of Birds from Transport Containers . . . . . . . . . . 3.2.3 Inversion and Shackling of Live Birds . . . . . . . . . . . . . . . 3.2.4 Impact of Acute Stress on Poultry Quality . . . . . . . . . . . . 3.3 Sheep . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.1 Flocking and Following Instinct . . . . . . . . . . . . . . . . . . . 3.3.2 Loading and Unloading . . . . . . . . . . . . . . . . . . . . . . . . . 3.3.3 Restraint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4 Cattle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.4.1 Movement of Cattle to the Point of Bleeding/Stunning . . . 3.4.2 Race Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

49 49 51 53 55 55 58 59 60 62 62 64 65 69 xxi

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4

5

Contents

3.4.3 Restraint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.5 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

71 81 82

Religious Slaughter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1 Slaughter Without Stunning: A Historical Account and the Current Situation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2 Historical Background on Slaughter Legislations and the Development of Stunning Technologies . . . . . . . . . . . . . . . . . . . . 4.2.1 Nape-Stab/Stab-Nape . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.2 Poleaxe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.3 Kleinschmidt Apparatus . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.4 Slaughter Masks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.5 Captive Bolt Guns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.6 Behr Flash Cattle Killer . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.7 Free Bullet Firearms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.8 Greener Humane Cattle Killer . . . . . . . . . . . . . . . . . . . . . 4.2.9 Greener Safti Killer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.10 RSPCA Humane Killer . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.11 Webley and Scott Speary Humane Killer . . . . . . . . . . . . . 4.2.12 Shotguns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.2.13 Other Stunning Methods . . . . . . . . . . . . . . . . . . . . . . . . . 4.3 Halal Slaughter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.1 Halal Slaughter: A Historical Background . . . . . . . . . . . . 4.3.2 Pre-Islamic Arabia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.3 Islamic Arabia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.4 Influence of Technological Advancement on Islamic Dietary Provisions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3.5 Halal Slaughter: Acceptable and Prohibited Practices . . . . 4.3.6 The Tayyib Concept of Halal Meat Production . . . . . . . . . 4.3.7 The Welfare Debate and How It Fits into Halal Slaughter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.4 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Socio-political Aspects of Religious Slaughter . . . . . . . . . . . . . . . . . . 5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.2 Growth of the Halal Market . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.3 Regulation and Certification of Halal Meat . . . . . . . . . . . . . . . . . . 5.4 The Rise of Anti-Halal Political Movements in the West . . . . . . . . 5.4.1 The Boycott Halal Movement . . . . . . . . . . . . . . . . . . . . . 5.4.2 The Ban Non-stun Slaughter Movement . . . . . . . . . . . . . 5.5 Ethical Considerations with Regard to Halal Meat Production . . . . 5.5.1 Animal Welfare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5.2 Environmental Sustainability . . . . . . . . . . . . . . . . . . . . .

88 95 101 101 104 105 106 108 108 110 110 112 113 114 114 115 119 120 121 124 126 131 137 139 140 145 145 147 149 151 152 156 168 170 170

Contents

5.5.3 Over-Production and Consumption . . . . . . . . . . . . . . . . . 5.5.4 Vegetarianism and Veganism . . . . . . . . . . . . . . . . . . . . . 5.6 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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171 173 174 175

Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

About the Author

Awal Fuseini holds a B.Sc. (Agriculture) degree from Cape Coast University in Ghana, M.Sc. (Meat Science and Technology) from Bristol University in the UK and a Ph.D. (Animal Welfare), also from Bristol University. Awal has extensive experience of the UK meat industry where he worked in a variety of roles, including auditing and managing certification activities for one of the largest Halal certification bodies in the UK. He also briefly worked as a consultant, during which time he provided services to food businesses and certifiers on issues around Halal meat production. Awal has published numerous scientific papers in several high impact peerreviewed journals, including Animals, Meat Science, Animal Welfare, Veterinary Record, Food Ethics, CAB Reviews and others. His work has been cited widely and attracted the attention of policymakers, politicians and the mainstream media. He is currently the Halal Sector Manager at the UK’s Agriculture and Horticulture Development Board (AHDB) and a Visiting Research Fellow at the University of Huddersfield Business School in the UK. His role at AHDB involves collaborating with key Halal stakeholders in the UK to create a better understanding of the Halal market with a view to adding value. As part of his role at AHDB, Awal also advises meat exporters on the requirements of different export markets and has been part of UK export missions to the Middle East and sub-Saharan Africa. Awal contributes to a number of meat industry working groups and currently co-chairs the Food Standards Agency’s Partnership Working Group—Work Stream 2 on the direct sale of Qurbani meat to Muslim consumers in the UK. In 2021, he was also named as an honorary associate by the British Veterinary Association (BVA).

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1

Introduction

Abstract

Anthropological evidence suggests that early bipedal ancestors of humans were consumers of animal protein, and this can be traced back as early as four million years ago. The contribution of animal protein to the advancement of human health cannot be underestimated; however, livestock agriculture has often been criticised for its impact on the environment and animal welfare. The consumption of highly processed meat has also been implicated in the causation of cancer, mainly due to the production of nitroso compounds (carcinogens) formed as a result of using nitrites and nitrates to process meat. To protect animal welfare, there are regulations in some countries which mandate that all animals must be stunned prior to slaughter to mitigate the pain associated with neck cutting. However, the requirement to stun prior to slaughter is inconsistent with the beliefs of some religious communities, particularly some Muslims and Jews.

Anthropological evidence suggests that early bipedal ancestors of humans were consumers of animal protein, and this can be traced back as early as four million years ago. Mann (2018) suggested that it was around this period that the human ancestral hominin line emerged from the African wetland forests to evolve into bipedal scavengers in the open grasslands. The transition to relatively drier, open grasslands meant that our ancestors had less access to readily digestible foods of plant origin; however, there were large numbers of grazing animals. This resulted in a dietary change: our ancestors began scavenging for the remains of herbivore carcasses (dead animals), but they later became more organised and established hunter-gatherer societies. According to Mann (2018), there is archaeological evidence to support the assertion that human ancestors were meat eaters; this is evidenced by cut marks left on animal bone remains and other paleoanthropological # The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 A. Fuseini, Halal Slaughter of Livestock: Animal Welfare Science, History and Politics of Religious Slaughter, Animal Welfare 22, https://doi.org/10.1007/978-3-031-17566-4_1

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evidence. Modern humans evolved from the hominin species as a result of years of metabolic and physiological adaptations resulting in dietary evolution, with meat taking a centre stage. Other researchers have suggested that early Hominids (e.g. Australopithecus africanus) subsisted mainly on fruits, leaves and grass (Sponheimer and Lee-Thorp 1999), while human ancestors initially survived largely on plant-based foods gathered from the wild (Ungar and Teaford 2002). Richards et al. (2003) pointed out that several studies on human dietary evolution reported a move away from the consumption of highly fibrous, low energy plant food sources to energy dense animal protein. The rate of the transition from hunting and gathering to domestication of crops and animals has been investigated. While some experts believe this was a gradual process lasting for up to a millennium (Dennell 1983), others are of the view that it was a rapid transition (Childe 1936). Richards et al. (2003) investigated this rate of change by measuring stable carbon isotopes in human bone collagen, with a focus on the Neolithic period and 3800 years preceding that. The researchers measured carbon isotopes in bone collagen of 19 Mesolithic and 164 early Neolithic British human remains (bones) and concluded that there was a rapid transition from hunting and gathering to the domestication of plants and animals. Klurfeld (2015) estimates that domestication of bovine animals dates back some 8500 years and suggests that there was an exponential increase in the utilisation of animal protein as a result of the transition from hunting and gathering to the domestication of crops and animals. The importance of meat consumption for the protection of human health and the eradication of hunger cannot be underestimated. Many experts have argued that improvements in human health can be achieved through the consumption of a balanced diet, with meat as a primary source of protein and other trace nutrients. Klurfeld (2015) reiterated the nutrient dense nature of meat by outlining some of the nutrients derived from meat as follows: high-quality protein, B-vitamins (particularly B6 and B12), zinc and haem iron. While some of these nutrients are available in plant-based foods, others, particularly vitamin B12, are mainly derived from meat or dairy products. It is worth noting that nutrients such as zinc, iron and vitamin B6 can be found in plant-based foods; however, their richest sources are animals and fish. Improvement in the quality of life through good nutrition and the eradication of hunger are two important components of the United Nation’s (UN) seventeen Sustainable Development Goals (SDGs). This is particularly significant in deprived communities in developing countries where ordinary people are unable to access three square meals a day in the right quantity and balance. Although meat is an important source of protein, it is expensive, so many people in developing countries are unable to afford it. At present, there are over a billion people, mainly in low- and middle-income countries, who are lacking protein and other nutrients due to starvation or the consumption of foods that are not balanced in nutrients. The author of this book has travelled to many countries around the world and, from his observations, countries in Africa and Asia appear to have the largest proportion of people living in food poverty. Fuseini and Sulemana (2018) carried out a survey of 915 meat eaters in Ghana and found that 61.46% of respondents who indicated that they rarely ate meat were simply unable to afford to buy meat on a regular basis. Many people in less

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affluent countries are facing malnutrition and starvation simply because they cannot afford a balanced diet. Arable and livestock agriculture can therefore ensure zero hunger and the sustenance of positive health outcomes within the human population. While meat consumption can lead to positive health outcomes, it is worth noting that it has been implicated in some health issues (Ungar and Teaford 2002). Even in the industrialised economies, there is evidence to suggest that in recent years there has been increased demand for food aid by poverty-stricken families living on state benefits or low income households (Lambie-Mumford and Dowler 2014). Rising food poverty has led to the prevalence of foodbanks in the United Kingdom and the United States as well as in other industrialised economies. Loopstra et al. (2015) reported that according to data from the UK’s Trussell Trust, a network of food banks, emergency food aid was provided to 900,000 adults and children between 2013 and 2014, representing a 163% rise from the previous year. Meat is heavily featured in the items donated to foodbanks and other charities. In 2021, Islamic Relief, a UK-based charity, donated seven tonnes of sheep meat to different organisations to distribute to the needy, and in the same year Euro Quality Lambs, an abattoir based in Shropshire, distributed 307 kg of sheep meat to 35 refugee families in the UK (Euro Quality Lambs 2021). In January 2022, Texas-based Church of Jesus Christ Latter Day Saints donated over 16 tonnes of meat and butter to a local foodbank, South Plains Foodbank (KCBD 2022). Meat donated to foodbanks is usually further distributed to families in need or cooked and served to the destitute, particularly homeless people. The situation with regard to food poverty has been exacerbated by the recent outbreak of the Coronavirus pandemic in late 2019/early 2020, which killed millions of people globally and threatened to put many economies into recession due to reduction in economic activities as a result of lockdowns in almost all countries of the world. Many have suggested that the virus probably originated from China, with some claiming it originated from the consumption of unconventional meat, particularly from the wet markets of Wuhan in China (Burki 2020; Riou and Althaus 2020), where the virus was first identified. Riou and Althaus (2020) reported that the Chinese authorities first alerted the World Health Organisation (WHO) on 31st December 2019, about what was described at the time as ‘a disease with no known aetiology’, with infected persons showing pneumonia-like symptoms. Scientists in China later identified the causative agent as a novel coronavirus, 2019-nCoV. By 29th January 2020, 68 cases were confirmed in a number of countries, with the number of confirmed cases in China hitting 5997 (Riou and Althaus 2020). With cases rising exponentially across the world in February and early March 2020, the WHO on 11th March 2020 declared the novel coronavirus a global pandemic. During his chaotic presidency, the former American president, Donald J. Trump repeatedly described the virus as the ‘Chinese virus’; in his view, the virus was intentionally unleashed by scientists in China. He repeatedly made statements to suggest that it could have been released by some people in China as a biological weapon. However, this claim has been dismissed by various sources (Andersen et al. 2020; Lawton 2020; Jaiswal et al. 2020).

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A number of scientific investigations into the nutritional components of meat have reported that meat is a vital source of proteins, amino acids, minerals, B-vitamins and other trace nutrients that are required in specified amounts for the formulation of sustainable diets (Font-i-Furnols and Guerrero 2014; Kauffmann 2001). In fact, some nutrients (e.g. vitamin B12) are reported to be present mainly in animal protein; however, many vegan foods (e.g. almond milk) do provide supplementary vitamin B12 (Kuhne et al. 1991). A vegan is a person who avoids the use of food (and non-food) products of animal origin, including all dairy products, honey, honey, milk, eggs, meat and others. Many vegans are well informed about these risks; however, nutrients lacking in vegan diets can be catered for by eating foods that are fortified with nutrient supplements. Madry et al. (2012) measured serum vitamin B12 concentration in 20 healthy adult omnivores who switched to vegan diets during a 5-year-long study. Ten participants were allocated to plant-based foods with no nutrient fortification, while the remaining ten were allowed to augment for the shortfall in some key nutrients by using foods fortified with nutrients or supplements. Samples were taken 6, 12, 24 and 60 months after they switched to full vegan diets, and the researchers found that there was a significant decrease in serum B12 concentration after 60 months from switching from omnivorous diet to veganism, particularly in the subgroup that did not have access to nutrient supplements. In another study, Gille and Schmid (2015) conducted an extensive literature review on the role of foods derived from ruminants; the review focused on the role of meat and milk as sources of vitamin B12 in human diets. The authors suggested that the consumption of 120 g portion of red meat is sufficient to meet the recommended daily intake of vitamin B12 (3 μg); similarly, the recommended daily intake of vitamin B12 can be met by drinking three glasses of ruminant (or plant) milk. It is generally agreed that unless vegans use vitamin B12 fortified foods, or vitamin supplements, they will not be able to meet the recommended daily intake of vitamin B12. Nonetheless, Watanabe et al. (2014) identified dried purple laver (nori) as a chief source of vitamin B12, iron and n-3 polyunsaturated fatty acids. According to the authors, dried purple laver is a natural plant which could address the nutritional deficiencies of vegan diets. Despite the apparent importance of meat and other animal by-products in providing vital nutrients required for the sustenance of life, many critics have consciously avoided meat altogether due to concerns for animal welfare, health (over-consumption resulting in obesity for example) and environmental sustainability (Goodland 1997; Bruers 2015). There are vegetarians who avoid meat simply because of the views they hold on animal rights, while others avoid meat due to concerns over the supposed inhumane treatment of animals. Others have avoided meat from certain species of animals for religious and cultural reasons. For instance, it is well documented that practising Muslims and Jews do not eat pork (Fuseini et al. 2019), while followers of the Hindu faith are prohibited from consuming beef. Although the majority of Hindus have chosen to avoid eating meat altogether, some Hindus do eat meat from other species of animals aside from beef, e.g. lamb and poultry (Sharma et al. 2003).

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The welfarist arguments can be viewed from two standpoints: the first group are those who avoid meat simply because they view the slaughter of animals as unacceptable, while the second group hold a view that all animals must be treated humanely during slaughter, e.g. using good handling and pre-slaughter stunning in order to mitigate the distress and pain associated with the slaughter process. As a consequence, Halal and Shechita slaughter without stunning have been the focus of discussions around animal welfare at slaughter for decades, with many groups repeatedly calling for religious slaughter without stunning to be outlawed. Halal slaughter is that carried out in line with Islamic principles while Shechita slaughter is performed in accordance with Jewish principles. The British Veterinary Association (BVA) and the Royal Society for the Prevention of Cruelty to Animals have long campaigned for slaughter without stunning to be outlawed. Some veterinary students in the UK become members of the BVA while studying towards their veterinary degrees. In an attempt to understand the views of veterinary students around slaughter (including slaughter with and without stunning) and to evaluate if their position differed from the BVA’s, the author of this book recently carried out a survey of veterinary students in four English universities with colleagues from Bristol University in the UK (Fuseini et al. 2019). The results indicate that the majority of veterinary students fall under the second group of welfarists (concern due to the lack of stunning of animals prior to slaughter). Nonetheless, a minority of the respondents indicated their support for slaughter without stunning for religious rites. Of the 459 students surveyed, 437 (95.2%) of the respondents indicated that they would want all animals to be stunned before slaughter, however, a minority of respondents, 5 (1.1%) indicated that religious slaughter should be exempt from stunning in order to cater for traditional religious values and customs, and to promote religious freedom. In a separate study, Fuseini et al. (2017) carried out a survey of Islamic scholars and Halal consumers in the UK and found that 69% of Islamic scholars did not believe stunning was capable of inducing unconsciousness. Some scholars commented that, in their opinion, stunning was a painful procedure and should not be used during Halal slaughter. As highlighted earlier, some religious authorities strongly believe that, when carried out correctly, religious slaughter without stunning can mitigate the pain and distress associated with pre-slaughter handling and neck cutting. This assertion is echoed by some researchers, including the renowned American Professor of Animal Science, author and designer of livestock systems, Temple Grandin. It must, however, be reiterated that there is overwhelming scientific data to suggest that slaughter without stunning compromises animal welfare (Gibson et al. 2009a, b; Johnson et al. 2014; Zulkifli et al. 2014). Within the EU, animal welfare legislation requires the stunning of all animals prior to slaughter. However, article 4/4 of EU Regulation on the Protection of Animals at the Time of Killing (PATOK), EC1099/2009, makes provision for member states to apply a derogation permitting slaughter without stunning for religious slaughter (described as ‘religious rite’ in the legislation). While some EU member states have applied the derogation (e.g. France, Germany, Poland and Ireland), others have chosen not to (Denmark, Slovenia and Sweden). This topic

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will be covered extensively in Chap. 4, where the situation in some member states is highlighted. Outside of the EU, slaughter without stunning is widely practised, including in the USA, Canada, all countries in the developing economies and Muslim-majority countries. According to the RSPCA, it is illegal to slaughter animals without stunning in Australia, with the exception of a handful of abattoirs that have been granted exemption (The Food Regulation Standing Committee 2007). According to New Zealand’s Animal Welfare (Care and Procedures) Amendment Regulations (2020), all commercial slaughter must be performed with stunning, including during religious slaughter. This book aims to highlight the welfare aspects of pre-slaughter handling and neck cutting and how these events are relevant to religious slaughter. It further examines the intricacies of conventional and religious slaughter with particular emphasis on the science of conscious perception and death from slaughter perspective, animal welfare and ethical considerations, and how the slaughter debate has been polarised by entrenched ideologies of political movements such as the Boycott Halal Movement in Europe, America and Australia. The humane aspects of both slaughter methods (slaughter with and without stunning) have also nonetheless divided the opinion of researchers. Chapter 2 examines the science of conscious perception and death with emphasis on synaptic transmission, consciousness, unconsciousness and death. Furthermore, various methods used in assessing unconsciousness and death are discussed as well as the different commercially available methods of stunning. In Chap. 3, pre-slaughter handling of small and large ruminants and poultry are discussed, with emphasis on the welfare aspects of different handling techniques. Chapter 4 focuses on religious slaughter with emphasis on Halal slaughter. It examines the historical background of Halal slaughter as well as the practice of slaughtering animals with and without stunning. The requirements of Halal slaughter and the concept of Tayyib during Halal meat production are explained in greater detail. The socio-political aspects of Halal meat production are covered in Chap. 5. It highlights the factors responsible for the continued growth of the global Halal market as well as the regulation and certification of Halal food production. The rise in anti-Halal political movements in some countries in the West is also discussed in this chapter, as well as the ethical aspects of Halal meat production. While the author acknowledges the economic and ethical significance of the Kosher market, the book focuses on Halal meat production.

Bibliography Andersen KG, Rambaut A, Lipkin WI, Homes EC, Garry RF (2020) The primal origin of SARSCoV-2. Natl Med 26:450–452 Animal Welfare (Care and Procedures) Amendment Regulations (2020) Code of Welfare: Commercial Slaughter. Amendments inserted on 9 May 2021 by notice in Gazette 2021-go1589 Bruers S (2015) The core argument for veganism. Philosophia 43:271–290 Burki T (2020) Outbreak of coronavirus disease 2019. The Lancet. https://www.thelancet.com/ pdfs/journals/laninf/PIIS1473-3099(20)30076-1.pdf. Accessed 20 Jan 2022 Childe VG (1936) Man makes himself. Watts, London

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Dennell RW (1983) European economic pre-history. Academic, London Euro Quality Lambs (2021) Charity Qurbani review 2021. https://euroqualitylambs.co.uk/halalblog/2021/12/charity-qurbani-review-2021/. Accessed 22 Jan 2022 Font-i-Furnols M, Guerrero L (2014) Consumer preference, behavior and perception about meat and meat products: an overview. Meat Sci 98(3):361–371 Fuseini A, Sulemana I (2018) An exploratory study of the influence of attitudes toward animal welfare on meat consumption in Ghana. Food Ethics 2:57–75 Fuseini A, Wotton SB, Hadley PJ, Knowles TG (2017) The perception and acceptability of pre-slaughter and post-slaughter stunning for Halal production: the views of UK Islamic scholars and Halal consumers. Meat Sci 123:143–150 Fuseini A, Grist A, Knowles A (2019) Veterinary students’ perception and understanding of issues surrounding the slaughter of animals according to the rules of Halal: a survey of students from four English Universities. Animals 9(6):293 Gibson T, Johnson CB, Murrell JC, Hulls CM, Mitchinson SL, Stafford KJ (2009a) Electroencephalographic responses of halothane-anaesthesised calves to slaughter by ventral neck incision without prior stunning. N Z Vet J 57(2):77–83 Gibson T, Johnson CB, Murrell JC, Chambers JP, Stafford KJ, Mellor DJ (2009b) Amelioration of electroencephalographic responses to slaughter by non-penetrative captive-bolt stunning after ventral-neck incision in halothane-anaesthetised calves. N Z Vet J 57:96–101 Gille D, Schmid A (2015) Vitamin B12 in meat and dairy products. Nutr Rev 73:106–115 Goodland R (1997) Environmental sustainability in agriculture: diet matters. Ecol Econ 23:189– 200 Jaiswal J, LoSchiavo C, Perlman DC (2020) Disinformation, misinformation and inequality-driven mistrust in the time of COVID-19: lessons unlearned from AIDS denialism. AIDS Behav 24: 2776–2780 Johnson CB, Mellor DJ, Hemsworth PH, Fisher AH (2014) A scientific comment on the welfare of domesticated ruminants slaughtered without stunning. N Z Vet J 63:58–65 Kauffmann RG (2001) Meat composition. In: Hui YH, Nip WK, Rogers RW, Young OA (eds). Marcel Dekker, New York, pp 1–19 KCBD (2022) South Plains foodbank receives 36000 pounds of meat. https://www.kcbd. com/2022/01/22/south-plains-food-bank-receives-36000-pounds-meat-lds-church/. Accessed 22 Jan 2022 Klurfeld DM (2015) Research gaps in evaluating the relationship of meat and health. Meat Sci 109: 86–95 Kuhne T, Bubl R, Baumgartner R (1991) Maternal vegan diet causing a serious infantile neurological disorder due to vitamin B-12 deficiency. Eur J Paediatrics 150:205–208 Lambie-Mumford H, Dowler E (2014) Rising use of “food aid” in the United Kingdom. Br Food J 116:1418–1425 Lawton G (2020) Still no evidence that the coronavirus was made in a lab. https://www.ncbi.nlm. nih.gov/pmc/articles/PMC7837135/. Accessed 20 Jan 2022 Loopstra R, Reeves A, Stuckler D (2015) Rising food insecurity in Europe. Lancet 385:2041–2042 Madry E, Lisowska A, Grebowiec P, Walkowiak J (2012) The impact of a vegan diet on B12 status in healthy omnivores: five-year prospective study. Acta Scientiarum Polonorum Technologia Alimentari 11:209–212 Mann NJ (2018) A brief history of meat in the human diet and current health implications. Meat Sci 144:169–179 Meat Industry Association (MIA) (2022) Halal. https://www.mia.co.nz/what-we-do/trade/halal/. Accessed 21Jan 2022 Richards MP, Schulting RJ, Hedges RE (2003) Archaeology: sharp shift in diet at onset of the neolithic. Nature 25:425 Riou J, Althaus CL (2020) Pattern of early human-to-human transmission of Wuhan 2019 novel coronavirus (2019-nCoV), December 2019 to January 2020. Rapid Commun 25. https://www. eurosurveillance.org/docserver/fulltext/eurosurveillance/25/4/eurosurv-25-4-2.pdf?expires=1

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642803894&id=id&accname=guest&checksum=46F9C36C724427D35CBEE418365E4444. Accessed 20 Jan 2022 Sharma JB, Soni D, Murphy NS, Malhotra M (2003) Effect of dietary habits on prevalence of anaemia in pregnant women in Delhi. J Obstetrics Gynaecol Res 29:73–78 Sponheimer M, Lee-Thorp JA (1999) Isotopic evidence for the diet of an early hominid, Australopithecus africanus. Science 283:368–370 The Food Regulation Standing Committee (FRSC) (2007) Australian standard for the hygienic production and transportation of meat and meat products for human consumption; AS4996: 2007. CSIRO Publishing, Collingwood Ungar PS, Teaford MF (2002) Perspective on the evolution of human diet. In: Human diet – its origin and evolution. Bergin and Garvey Publication, Connecticut Watanabe F, Yabuta Y, Bito T, Teng F (2014) Vitamin B12-containing plant food sources for vegetarians. Nutrients 6:1861–1873 Zulkifli I, Goh Y, Norbaiyah B, Sazili A, Lotfi M, Soleimani A, Small A (2014) Changes in blood parameters and electroencephalogram of cattle as affected by different stunning and slaughter methods in cattle. Anim Prod Sci 54(2):187–193

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The Science of Conscious Perception and Death

Abstract

This chapter examines the science of conscious perception and death with emphasis on synaptic transmission, consciousness, unconsciousness and death. Furthermore, various methods used in assessing unconsciousness and death are discussed as well as the different commercially available methods of stunning. An understanding of the anatomy and neurophysiology of food animals is vital to understanding pain perception during slaughter, the significance of exsanguination in promoting death and the conversion of the carcass to meat. This chapter may be useful to veterinarians, animal welfare scientists, competent authorities, abattoir workers and religious authorities who have a collective interest of protecting animal welfare during slaughter.

An understanding of the anatomy and neurophysiology of food animals is vital to understanding pain perception during slaughter, the significance of exsanguination in promoting death and the conversion of the carcass to meat. The pain associated with neck cutting and measures for mitigating the pain (e.g. pre-slaughter stunning) have been extensively investigated (Wotton et al. 2000; Gibson et al. 2009a and others). The general consensus is that, if neck cutting is performed without any form of pain-mitigating interventions (e.g. pre-slaughter stunning), animals can perceive the neck cut as a noxious stimulus. Gregory et al. (2010) examined the time taken for 174 cattle to collapse following slaughter without stunning (restrained in their natural standing position), they found the average time to final collapse to be 20 s. Those cattle that developed false aneurysms (71%) took more than 75 s to collapse. Time from neck cut to collapse is important in assessing animal welfare during slaughter because it is an indicator of the initiation of the loss of consciousness (Velarde et al. 2007). The exact time at which cattle lose consciousness during slaughter without stunning is still not well understood (Johnson et al. 2014), there # The Author(s), under exclusive license to Springer Nature Switzerland AG 2023 A. Fuseini, Halal Slaughter of Livestock: Animal Welfare Science, History and Politics of Religious Slaughter, Animal Welfare 22, https://doi.org/10.1007/978-3-031-17566-4_2

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have been conflicting results presented by different scientists using behavioural or electroencephalographic approaches, or a combination of both (Gregory et al. (2010). While some researchers have reported appreciably longer duration, others have found that calves lose consciousness more promptly. For instance, Daly et al. (1988), Grandin (2010) and Verhoeven et al. (2015) reported that calves remain conscious after 17 s and up to 85 s after the neck cut (without stunning). Bager et al. (1992) slaughtered six calves without stunning and reported that five out of the six calves lost consciousness within 10 s, one calf was found to show some signs of consciousness after 52 s. The researchers later found that the calf that showed delayed loss of consciousness had developed false aneurysms. When evaluating the time to loss of consciousness in cattle and calves, it is important to inspect the cut ends of the carotid arteries to ensure that blood flow is not obstructed, this can significantly extend the time to loss of consciousness. Johnson et al. (2014) suggested that based on knowledge of the pain associated with slaughter without stunning in cattle (see Gibson et al. 2009a, b; Murrell and Johnson 2006), it can be concluded that sheep and goats would experience pain when slaughtered without stunning. The time to loss of consciousness in sheep following slaughter without stunning has been reported to be between 2 and 20 s (Nangeroni and Kennett 1963; Blackmore 1984). Where animals are stunned prior to slaughter, it is important to understand that the mechanisms of the induction of unconsciousness differ from one stunning method to another. It is also worth reiterating that the success of a stunning method may be influenced by animal, operator and operational factors. Terlouw et al. (2016a) explained that the mechanism of the induction of unconsciousness depends on whether animals are stunned mechanically, electrically or with gaseous mixtures. The authors elaborated that, even when animals are slaughtered without stunning, unconsciousness does occur at some point before death. This implies that loss of consciousness always precedes death, whether animals are stunned or not. The difference between unconsciousness during slaughter with and without stunning is that, whilst unconsciousness as a result of stunning can be almost immediate (with the exception of gas stunning and low atmospheric pressure stunning), there can be a delay in its induction (from a few seconds to several minutes) during slaughter without stunning. This is, however, disputed by some religious authorities who insist that slaughter without stunning is a painless process. It is also worth noting that the anatomy and physiology of blood flow differ from one species to the other, and this can affect the time between the neck cut and induction of unconsciousness during slaughter without stunning. In addition to the carotid arteries, cattle have sufficiently developed vertebral arteries which run along the back of the neck and carry oxygenated blood to the brain. In small ruminants (e.g. sheep and goats), the main route of blood movement to the brain is through the carotid arteries. To protect the welfare of animals, EU legislative requirements (EC1099/2009) dictate that all methods of stunning must not be aversive. This is intended to mitigate the pain associated with the neck cut. However, carbon dioxide stunning at high concentration has been found to be aversive; despite this, it is widely used within the EU to stun pigs and poultry.

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Some researchers have argued that the act of slaughter itself, whether with or without stunning, can never be humane. Browning and Veit (2020) argued that the slaughter of farm animals can never be ‘truly humane’, their reasoning for this assertion being that slaughter can only be described as humane if there is guarantee that the whole life of the animal is protected from harm, from the day it is born or hatched to the point of death. The authors further explained that death itself is a compromise to the welfare of the animal because it deprives the animal of the opportunity to experience positive events in the future. This line of argument is echoed by some non-meat eaters and animal welfare advocates. This chapter considers the functions of the brain in the control of conscious perception, assessment of unconsciousness and death. Various commercially available stunning techniques are also explored.

2.1

Neural Communication

This section attempts to explain neural communication and examines the scientific basis for the induction of unconsciousness via the application of stunning equipment. While this is a technical subject, the author aims to simplify it for the understanding of Islamic scholars and Halal consumers (as well as scientific readers), so that they can make informed decisions on issues surrounding the compatibility of certain slaughter techniques with Halal meat production and the impact of those techniques on animal welfare. The author would like to highlight the fact that this subject is a broad one; however, attempts have been made to cover the salient points based on the areas in which the author thinks more clarity is needed. The following sections look at how brain cells (neurons) communicate with each other to maintain conscious perception and how the mode of communication (synaptic transmission) can be disrupted to induce unconsciousness.

2.1.1

Neurons

A neuron or brain cell is simply the basic working unit of life in the brain or the nervous system in general. The brain is made up of over 85 billion neurons; these are sometimes referred to as nerve cells and they play an important role in maintaining conscious perception. Neurons transmit information to other neurons, gland cells and muscles in different parts of the body. An understanding of the structure and functioning of the neuron is therefore vital in understanding the concept of consciousness, unconsciousness and death during the slaughter of food animals. Neurons generally consist of a cell body, fibre-like branches called dendrites and an axon which emerges from the dendrites (see Fig. 2.1). Dendrites originate from the cell body and play a role in receiving information from adjoining neurons as well as facilitating the transmission of signals to the cell body through the dendritic spine. The dendritic spines are the protrusions from the ends of dendrites. The cell body is

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Fig. 2.1 Illustration of parts of a neuron: brain cell

similar to an engine of a car, in that it controls all functions of the neuron as well as housing the nucleus and endoplasmic reticulum in the cytoplasm. The function of the axon is to send information to other nerve cells. It is a slender projection which emanates from the cell body at a junction called the axon hillock, and it branches further into axon terminals. The axon terminal houses minute vesicles containing neurotransmitters (see types and functions of neurotransmitters in Sect. 2.1.2, Synaptic transmission).

2.1.2

Synaptic Transmission

Neurons communicate with one another (or with muscle cells) at the neuronal junction known commonly as the synapse, through the transmission of signals in order to maintain conscious perception in human and non-human animals. Communication between neurons is effected through the transfer of chemicals (neurotransmitters) from one neuron to the other. The neuron from which the neurotransmitter originates is called a pre-synaptic neuron and the receiving neuron

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Fig. 2.2 Illustration of neural transmission between a pre-synaptic and post-synaptic neuron. The image highlights the synaptic cleft, synaptic vesicles and neurotransmitters

is called a post-synaptic neuron. The neurotransmitters are contained in vesicles called the synaptic vesicles, with each vesicle containing thousands of neurotransmitter molecules. The neurons interact in such a way that they never come into direct contact with one another; there is a microscopic space maintained between neurons, called the synaptic cleft. Figure 2.2 illustrates neural transmission between the pre-synaptic and post-synaptic neurons, highlighting the synaptic cleft, synaptic vesicles and neurotransmitters. During neurotransmission, an action potential is generated at the axon hillock in the pre-synaptic neuron to induce the vesicles containing neurotransmitters to fuse with the membrane of the pre-synaptic neuron, resulting in the release of the contents of the vesicles (neurotransmitters) into the synaptic cleft. The neurotransmitters then react to receptors on the post-synaptic neuron in order to bind to the membrane of the post-synaptic neuron. The binding of neurotransmitters onto receptors on the postsynaptic neuron leads to the flow of ions across the post-synaptic membrane, and this completes a cycle of communication or transmission of a signal. These events occur very rapidly, within a fraction of a second. In a normally functioning brain, an ionic balance and equilibrium of neurotransmitters is established across neural membranes. There are several neurotransmitters, all performing different roles during neurotransmission. Raj

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Table 2.1 Main neurotransmitters in the brain and the roles they play Neurotransmitter GABA Glutamate

Aspartate (C4H7NO4) Dopamine (C8H11NO2) Serotonin (C10H12N2O) Norepinephrine (C8H11NO3) Acetylcholine (C7H16NO2) Endorphin (C77H120N18O26S)

Function An inhibitory amino acid involved in the reduction of neural excitation, resulting in the inhibition of the firing of brain cells (neurons) An excitatory amino acid involved in biosynthesis of proteins to strengthen synaptic connections. This is a non-essential amino acid and there are five different types of glutamate receptors An excitatory amino acid involved in biosynthesis of proteins (precursor). It is a non-essential amino acid used in mitigating depressive states in the brain A catecholamine that has several functions; it can function as a hormone or a neurotransmitter. As a neurotransmitter, it is involved in controlling movement and arousal A neurotransmitter involved in the regulation of memory, mood, sleep, eating and digestion A stress hormone that is usually released into the blood when the brain processes a stressful event. It also doubles as a neurotransmitter involved in learning, mood regulation and arousal A neurotransmitter involved in muscle contraction, memory, pain responses and the regulation of cardiac rhythm. It is usually released by the pre-synaptic terminals of cholinergic neurons Endorphins bind to opiate receptors in the brain to moderate painful experiences, and are often described as natural pain and stress fighters

(2003) noted that neurotransmitters are categorised into inhibitory and excitatory categories, and these must maintain a state of equilibrium in order to maintain conscious perception. Any deviation in the concentration of inhibitory and excitatory neurotransmitters can lead to anomalies such as depression or the sensation of anoxious stimulus. Aspartate and glutamate are examples of excitatory amino acids, whilst Gamma aminobutyric acid (GABA) is an inhibitory amino acid. Table 2.1 highlights the major neurotransmitters in the brain and their functions. When an animal is exposed to a noxious stimulus, pain receptors (nociceptors) at the location of contact send nociceptive nervous messages to the brain through a network of nerves in the body and then to specific structures in the brain, including limbic and somatic sensory cortices. The limbic cortex is involved in the interpretation of complex painful signals received from pain receptors, whilst the somatosensory cortex processes signals with regard to the type, intensity and location of the insult. Murrell and Johnson (2006) demonstrated the perception of pain during slaughter through the use of EEG recordings. Terlouw et al. (2016a) explained that noxious stimuli include the following: tissue lesions, chemical, mechanical and thermal types of stimulation that elicit a response and transmit signals to the brain. It is against this background that the majority of researchers have concluded that the slaughter of animals without stunning can be perceived as a noxious stimulus, due to the network of nociceptors around the neck (see Gibson et al. 2009a, b and others). To mitigate the pain associated with noxious stimuli, various methods of stunning have been developed. For instance, the application of voltage to the head (and

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through the brain) can alter the equilibrium of inhibitory-excitatory neurotransmitters, leading to the disruption of ‘normal’ neurotransmission, brain function and consciousness. The disruption of the inhibitory-excitatory neurotransmitter balance through the release of neurotransmitters leads to epileptiform seizures in the brain, resulting in the induction of brain dysfunction and insensibility.

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Non-human mammalian animals are sentient beings due to their capacity to experience both positive and negative emotive states (Boissy et al. 2007); this is because they possess the limbic system in their brains. The limbic system has been identified in the human brain to be the main structures responsible for the control of emotions, memory, motivation and learning. The system is a set of cortical structures located just above the brainstem and beneath the medial temporal lobe, at both sides of the thalamus, and sometimes referred to as the paleomammalian cortex. Balanoff et al. (2013) suggested that, although birds have brains that differ structurally from human and non-human mammals, they also possess structures that function similarly to the limbic system in the mammalian brain, so they also experience positive and negative emotions.

2.2.1

Consciousness

It is generally accepted that consciousness is the ability of human and non-human animals to be aware of their environment, immediate and external world (Zeman 2001). However, despite years of studying conscious perception by philosophers and scientists, the true meaning of consciousness still divides opinion. Van Gulick (2004) echoed this by suggesting that there are some differences of opinion between philosophers as to the true definition of consciousness. Due to these differences among philosophers, Schneider and Velmans (2008) described consciousness as a concept of life that philosophers are very familiar with, but is yet very mysterious. Searle (2005), on the other hand, reported that one area of agreement is the intuition that consciousness exists, and that no one appears to deny the existence of the concept of consciousness. In the global Halal arena, there appears to be confusion with regard to the use of the words ‘conscious’ and ‘alive’. This is because many Muslims insist on animals being fully conscious during slaughter, however, the Quran, Hadith and Sunnah, from which the dietary laws are derived, only make reference to the fact that animals must be alive at the point of slaughter. In fact, the author of this book is aware of consumers who believe that animals in a state of unconsciousness are actually dead, implying that the meat derived from such animals cannot be consumed by Muslims. To illustrate the difference between the two events (alive and conscious), it is important to point out that an animal can be in a state of unconsciousness and still be alive at the same time; on the other hand, a conscious animal is always alive

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because consciousness is about awareness, and to be aware, an animal must be alive (see Sect. 2.1, Neural communication, above). Introducing ‘death’ into the picture brings in a completely different dimension; a dead animal is neither conscious nor alive because death is defined as the irreversible loss of brain function (Fuseini 2019a). Irreversible loss of brain function implies that the brain is essentially dead, therefore the animal is neither conscious nor alive. A further explanation of this would be the comparison of pre-slaughter stunning with the use of general anaesthesia. If an animal is effectively stunned, it is essentially knocked unconscious; however, depending on the method of stunning used, the animal will usually not die as a consequence of the stun, and this implies that even though the animal is in a state of unconsciousness (as a consequence of the stun), it is still alive (not brain dead). It must be noted that there are some methods of stunning that will induce cardiac fibrillation (cardiac arrest), and this can result in brain death. Electrical head-to-body stunning is an example of a method of stunning that would induce cardiac fibrillation (cardiac arrest). In this case, the animal is first stunned to induce unconsciousness, followed immediately with cardiac fibrillation to stop the heart. The stoppage of the heart prevents oxygenated blood from moving from the heart to the brain, resulting in brain death. As a consequence, the majority of Halal certifiers do not approve this method of stunning. Zeman (2005) reported that consciousness is a complex phenomenon, and understanding the concept of consciousness requires the identification of two distinct components: the level of wakefulness (level of consciousness) and the awareness of the environment and the deeper state (content of consciousness). Content of consciousness is controlled by the cerebral cortex and relates to an animal’s selfawareness and ability to perceive a noxious stimulus. It is this component of consciousness that is most relevant when discussing the pain associated with slaughter. Level of consciousness, on the other hand, relates to the function of the reticular formation in the control of awareness (or alertness), arousal and sleep. The reticular formation is a network of neuronal structures that extends from the spinal cord to the thalamus, with connections through the brainstem (pons, medulla oblongata and midbrain). Figure 2.3 shows the structure of the brain, highlighting the reticular formation and midbrain. Terlouw et al. (2016a) explained that the reticular formation and some structures of the pons project to the cortex to facilitate the efficient functioning of the cortex. Block (1998) categorised consciousness into two distinct types; access (or A-consciousness) and phenomenal (or P-consciousness). The author explained the concept of A-consciousness as the ability of the mind to access information to aid our reasoning, memory and to control our behaviour. For instance, our ability to recall past events (e.g. a wedding ceremony that took place ten years ago) is classed as access consciousness. P-consciousness, on the other hand, describes our ability to perceive changes in our immediate surroundings, for instance, the ability of animals to perceive emotions, sounds and sensations. For the purpose of discussions on animal welfare at slaughter, it is P-consciousness that is of relevance. Whether animals are being transported, lairaged, restrained or bled, they are constantly exposed to stressors that require P-consciousness.

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Fig. 2.3 Structure of the brain highlighting the reticular formation and constituents of the brainstem

2.2.2

Unconsciousness

Unconsciousness is the opposite of consciousness; it is the loss of awareness of the environment due to permanent (irreversible) or temporary (reversible) loss of brain function. In this book and other scientific literature, the term unconsciousness is used interchangeably with the term insensibility. Blackmore and Delany (1988) clarified that some researchers prefer using insensibility to unconsciousness because they believe it is less anthropomorphic. The European Food Safety Authority (EFSA 2006) explained that temporary or permanent loss of brain function implies that animals lack the capacity to feel a stimulus (e.g. pain). When used in relation to the slaughter or killing of animals, unconsciousness describes the period during which an animal can no longer feel the pain associated with the slaughter process, i.e. hoisting, neck cutting and post-neck cut operations. Pain is difficult to quantify; however, the concept of pain has been widely researched. Merskey (1986) defined pain as, ‘an unpleasant sensory and/or emotional experience associated with actual or potential tissue damage or described in terms of such damage’. Broom (2001) on the other hand defined pain as ‘an aversive sensation or feeling associated with actual or potential tissue damage’. The nervous system of animals in a state of unconsciousness become dysfunctional, and in this state, the brain is no longer able to process sensory information, so animals become unaware of painful and emotional

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sensations. As noted above, stunning is commonly used to induce unconsciousness prior to slaughter (neck cutting); however, to prevent the recovery of animals and ensure irreversible loss of brain function, stunning is usually followed immediately by a secondary intervention (e.g. exsanguination). The major blood vessels in the neck are usually severed in order to cause sufficient blood loss to deprive the brain of its oxygen requirement. Depending on the method of stunning used, unconsciousness may be induced through depolarisation of neurons (electrical stunning), concussion and physical destruction of neurons (mechanical stunning) or creation of an anoxic state and acidification in the brain (gas stunning).

2.2.3

Death

Death is defined as the irreversible loss of function of the brainstem (Pallis 1995). Within the Islamic scholarly fraternity, there is no unified definition of death. However, Muslims are commanded by God not to eat meat from animals that have died prior to slaughter, as highlighted below in chapter 2 of the Holy Quran (and others): He has only forbidden to you dead animals, blood, the flesh of swine, and that which has been dedicated to other than Allah (God). But whoever is forced (by necessity), neither desiring (it) nor transgressing (its limit), there is no sin upon him. Indeed, Allah is Forgiving and Merciful (Quran 2:173).

It is clear from the verse above that the consumption of meat from animals that have already died is prohibited for Muslims. However, what is open to interpretation is whether the verse is referring to animals that have died a natural death or whether it extends to animals that die as part of the slaughter process, prior to bleeding (e.g. irreversible stunning to kill). Some Muslims have argued that the verse is probably referring to animals that die naturally or through other non-slaughter related incidents such as road kills, animals that die on arrival at the abattoir (DoA), animals that die as a result of diseases, animals killed by other animals, animals that die as a result of a headlong fall and those that die as a consequence of strangulation. The author is aware of the use of irreversible stunning methods during Halal slaughter in Europe. There are abattoirs in the UK (FSA 2018) and Sweden (Berg and Jakobsson 2007) that use penetrative captive stunning for Halal meat production. Controlled atmosphere stunning is also in use in the Netherlands, Germany and other countries within the EU. Opponents of pre-slaughter stunning have often maintained that stunning is inconsistent with Halal slaughter because it can lead to the death of animals prior to exsanguination. There is, however, less clarity on what death actually means in the context of religious slaughter. In a recent review paper examining the differences in the definition of death within the Muslim scholarly fraternity, the author of this book highlighted the fact that some Muslims base the definition of death on the irreversible cessation of the function of the heart

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(Fuseini 2019a). It has been reported that diagnosis of death based on the function of the heart (cardiorespiratory death) was common in ancient Egypt and Greece, where the presence of a beating heart was associated with vital spirits and death was only confirmed when the heart ceased beating (Pernick 1988). Scholars who define death in relation to a functioning or beating heart would usually use post-stun convulsions as behavioural indicators of life or the absence of death. Grandin (2015) noted that this method of diagnosing death is still common within the Muslim community, particularly during Halal slaughter, but pointed out that, after animals have irreversibly lost brain function (died), their heart will continue to beat for between 8 and 10 min. This implies that, even though some Muslim authorities use the presence of a beating heart as evidence that animals are alive, this may not be an accurate diagnosis of death. From his interactions with stakeholders within the Muslim community in the UK and across Europe, the author of this book has found that Muslims who define death based on the function of the heart tend to accept irreversible stunning (gas and penetrative captive bolt stunning methods for instance) as Halal-compliant. They hold a view that, provided there is a beating heart prior to neck cut, the meat would be Halal, and this practice is common during Halal slaughter in Germany, the Netherlands and other EU member states. On the other hand, there are Muslims who define death based on the function of the brain (a neurocentric definition of death). This criterion of diagnosing death is an internationally accepted medical definition used throughout the world. Laureys (2005) reported that the first scientist to suggest a neurocentric diagnosis of death (death based on the functioning of the brain) was a medieval Jewish academic by the name of Moses Maimonides (1135–1204). One of the reasons why Moses adopted the neurocentric diagnosis was the fact that he observed convulsions and the presence of a beating heart in decapitated humans and concluded that the presence of a beating heart did not adequately provide the basis for the accurate diagnosis of death. One of the challenges of diagnosing death in humans, based on the function of the brain, as pointed out by Orban et al. (2015), is that it can cause the family of the deceased a great deal of distress, particularly when the brain irreversibly loses its function and some limbs are still moving. Physicians have reported having a great deal of difficulty in trying to explain to families of the dead that any movements by the ‘patient’ after they have been diagnosed dead (brain death) are merely caused by spinal reflexes and do not represent ‘life’ in the ‘patient’ (Kerridge et al. 2002). Halal certification bodies who have adopted the neurocentric definition of death have cautiously avoided stunning methods that are likely to cause brain death. The two methods of diagnosing death are relevant in discussions on religious slaughter. Islamic scholars need to come to a consensus as to which definition is acceptable from a religious standpoint, and this will resolve the impasse on the acceptability of some slaughter technologies (e.g. pre-slaughter stunning). Those who define death based on the irreversible loss of function of the brain (neurocentric death) are unlikely to accept penetrative captive bolt stunning, for instance, due to the gross damage to the brain inflicted by the penetrating bolt. Muslims who favour the neurocentric definition of death are more likely to accept electrical head-only stunning or no stunning at all. Those who define death based on the functioning of

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the heart (cardiorespiratory death) are more likely to accept irreversible stunning as long as there is a beating heart post-stunning.

2.2.4

Assessment of Unconsciousness

To ensure that animals remain unconscious during slaughter until death supervenes, animals that have been effectively stunned must be continuously monitored for any signs of recovery from unconsciousness. This monitoring must be done on each and every stunned animal to identify those that may not have been stunned effectively (including mis-stuns) and those that quickly recover from short-lasting or reversible stunning techniques (e.g. electrical head-only stunning). Ineffective stunning may occur due to operator, animal or equipment factors. The operator may not be well trained or skilled in applying the equipment correctly, poor maintenance or servicing of stunning equipment may lead to equipment failure, leading to ineffective stunning, and the structure of the head of particularly large ruminants can reduce stun effectiveness too. For animals stunned during Halal meat production, there is an additional requirement for slaughter operatives to monitor the animal for any signs of death before bleeding. It is worth noting that diagnosing animals that have died as a consequence of stunning under commercial conditions is almost impossible. Furthermore, diagnosis of death on the slaughter line is not a legal requirement within the EU, but a religious one (see GSO 993). The situation is further complicated by the fact that there are differences of opinion as to the true definition of death within the Islamic scholarly fraternity, as discussed earlier (Grandin 2015; Fuseini 2019a). Animals slaughtered without stunning must also be monitored for loss of consciousness, and in the UK, there is a standstill time of 20 s and 30 s for small and large ruminants, respectively (WATOK 2015). This is interpreted to mean that animals slaughtered without stunning must not be moved until they lose consciousness, or in any case, they should not be moved until the expiration of the specified standstill times. Unconsciousness can be assessed objectively with an electroencephalogram (EEG), or by subjectively looking out for behavioural, brainstem or spinal reflexes. Aside from using EEG and behavioural indicators for assessing unconsciousness, Rodriguez et al. (2008) reported measuring blood parameters (oxygen saturation, pH, bicarbonate, oxygen and carbon dioxide partial pressures) to assess unconsciousness in pigs during carbon dioxide gas stunning. One of the shortfalls of objective assessment of unconsciousness during slaughter, either with the EEG technique or measuring blood parameters, is that it is almost impossible to use these methods under commercial conditions, and they are more suited for use in the laboratory. When assessing unconsciousness subjectively, a number of indices can be used. Outlined below are the various indicators that can be used to assess unconsciousness after stunning and/or neck cutting: • Behavioural indicators, e.g. loss of righting reflex or posture, absence of rhythmic breathing and vocalisation.

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• Brain and spinal reflexes, e.g. absence of eye reflex (brain reflex) and pedal reflexes (spinal reflex). Section 2.2.4.2 gives more information about reflexes. • Blood parameters, e.g. oxygen saturation, pH, bicarbonate, oxygen and carbon dioxide partial pressures (Gregory et al. 1987; Lomholt 1998; Martoft et al. 2001; Rodriguez et al. 2008). The types of indicators used may be influenced by the species/size of animal and method of stunning. For instance, Verhoeven et al. (2015) suggested that, for stunning methods that do not cause physical damage to the brain (such as electrical and gas stunning), unconsciousness is best assessed by considering natural blinking responses, the righting reflex, vocalisation and rhythmic breathing. The use of brainstem reflexes, such as the corneal reflex, as the only tool for assessing unconsciousness during electrical stunning is not advised, because an electrically stunned animal may exhibit residual brainstem activity in the form of a corneal reflex, which may be misinterpreted as consciousness. Verhoeven et al. (2015) further explained that, during mechanical stunning (e.g. penetrative and non-penetrative captive stunning), unconsciousness can be confirmed by indicators such as loss of posture, absence of rhythmic breathing, loss of the righting reflex and the absence of palpebral and corneal reflexes. It is difficult to employ spinal reflexes as indicators of unconsciousness during mechanical stunning. As a general rule of thumb, it is good practice to continuously monitor animals after stunning for signs of recovery from consciousness by using a combination of indicators instead of relying on a single indicator. Anil and McKinstry (1991) suggested that using the threat reflex alone to assess unconsciousness does not provide accurate assessment, in that positive eye reflexes on their own may be due to residual brainstem activity and do not necessarily mean the animal is conscious. According to Verhoeven et al. (2015), the threat reflex is the sudden involuntary reaction of an animal (through blinking or withdrawal) in response to a threat, for instance, directing an object towards the eye at speed.

2.2.4.1 Behavioural Assessment During slaughter with and without stunning, a number of behavioural indices can be used to assess when animals are in a state of unconsciousness and/or when they are recovering from it. Terlouw et al. (2016b) explained that post-stun behavioural indicators are associated with the function of the reticular formation and the cerebral cortex. EU legislative requirements (EC1099/2009) mandate a secondary stunning system (i.e. a back-up stunner) that must be kept in close proximity of the slaughter station so that it can be deployed to re-stun animals if they are showing signs of recovery from consciousness or if there is an incidence of a mis-stun. Where animals are slaughtered without stunning, the same rules apply: there must be a stunning system which must be deployed if animals are taking an abnormally long period of time to lose consciousness after neck cutting. Mechanical stunning systems (e.g. penetrative captive bolt) are commonly used as back-up stunners in EU abattoirs.

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When using behavioural indices to assess unconsciousness, care must be taken not to generalise certain behaviours to all animals, or for all methods of stunning. Some behaviours may be unique to certain species or methods of stunning. For instance, cattle, pigs and chickens will immediately vocalise when they are exposed to a noxious stimulus, but sheep are less likely to. Therefore, the absence of vocalisation alone cannot be used as confirmation of unconsciousness in all animals. Outlined in Table 2.2 are some behavioural indicators that can be employed in the assessment of consciousness during slaughter.

2.2.4.2 Brain and Spinal Reflexes Reflexes are responses to stimuli elicited in the central nervous system. Carlson (2007) described a reflex as an automatic reaction to a stimulus that is processed by the central nervous system (i.e. the brain, spinal cord and a network of nerves). Reflexes are generally categorised into brainstem reflexes and spinal reflexes. Brainstem reflexes are those that originate from the brain, whilst spinal reflexes originate from the spinal cord. The presence of reflexes may be an indication of consciousness; for instance, if an animal is able to react to threat, this may be an indication of consciousness and such animals are likely to feel the pain associated with slaughter. Some brainstem reflexes of relevance in assessing consciousness in animals during slaughter include pupillary reactivity to light and threat, corneal and palpebral reflexes and blinking. Table 2.3 shows some important reflexes that may be used in assessing consciousness during slaughter. As highlighted in the preceding sections of this book, it is important to use a combination of reflexes or behavioural indices in assessing consciousness. 2.2.4.3 Electrical Activity of the Brain As indicated above, it is possible to carry out an objective assessment of unconsciousness using EEG recordings under experimental conditions; however, this method is not suitable for use in commercial abattoirs due to line speeds and other factors. EEG electrodes are usually attached to the head (just above the brain) to record the electrical activity in the brain, and these electrodes can record any deviations from normal in the electrical pulses between brain cells (see Murrell and Johnson 2006; Gibson et al. 2009a, b; Martin et al. 2016). EEG recordings can be used to diagnose and interpret conditions in the brain such as epileptic seizures, cancerous tumours and other conditions of neuropathological significance, as well as death (relative to permanent loss of function of the brainstem). Martin et al. (2016) recorded the electrical activity of the brain using EEG recordings to evaluate the efficacy of a novel method of stunning, Low Atmospheric Pressure Stunning (LAPS). LAPS induces unconsciousness through progressive hypobaric (low pressure) hypoxia (deprivation from oxygen). The EEG recording is interpreted by considering various wave patterns, of which there are approximately four. The wave patterns are distinguishable by their respective frequencies; for instance, Kooi et al. (1978) reported that slow wave activity of frequencies between 0 and 8 Hz (δ and θ) have been found to be associated with reduced consciousness (e.g. sleep), whilst frequencies between 8 and 12 Hz (α) are usually associated

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Table 2.2 Outline of different behavioural indicators that are normally used in the assessment of consciousness during slaughter Behavioural indicator Loss of posture

Gasping and agonal breathing

Vocalisation

Explanation Loss of posture is generally agreed to be the initial sign of the onset of loss of consciousness after stunning. In other words, if an animal is effectively stunned, it cannot remain in its natural standing position and will immediately collapse. Terlouw et al. (2016b) reported that immediate collapse is an obvious sign that an animal has lost consciousness, but it must be interpreted with caution; animals may collapse for reasons other than loss of consciousness and the method of restraint (e.g. shackling of birds and the use of V-restraint for poultry) may prevent animals from collapsing. The recommendation is that collapse should not be used as the only indicator to assess loss of consciousness. The parts of the brain responsible for maintaining the righting reflex or natural posture are the cerebral cortex and the reticular formation (Llonch et al. 2013), and these parts of the brain become dysfunctional after effective stunning. AVMA (2013) and Terlouw et al. (2016b) have reported that, when applied correctly, both electrical and mechanical stunning should lead to immediate collapse of animals. Schepens and Drew (2004) suggested that immediate collapse following mechanical stunning is linked to damage to the reticular formation. In the case of gas stunning (and slaughter without stunning), there is no immediate collapse because unconsciousness is induced in a progressive manner as gases are inhaled (in the case of gas stunning) or related to deprivation of the brain of its oxygen requirement due to sufficient blood loss (in the case of slaughter without stunning) Gasping is an abnormal breathing pattern during which an animal takes deep breaths through an open mouth and should not be confused with rhythmic breathing. It is akin to agonal respiration or agonal breathing. Verhoeven et al. (2015) reported that, during carbon dioxide gas stunning, gasping is generally regarded as an indication of the initial phase of breathlessness, which can last until consciousness is lost and may even be observed when the brain is no longer functioning. Rodriguez et al. (2008) observed gasping after 23.5 s when pigs were exposed to carbon dioxide. Grandin (2013) explained that gasping is possible in animals that have been effectively stunned electrically. Grist et al. (2018) investigated the efficacy of using a non-penetrating captive bolt to euthanise neonate (kid) goats and found that two of the 158 goats displayed agonal breathing with no additional behavioural indication of brain function. The researchers concluded that agonal breathing was not associated with consciousness, but with residual brainstem activity. Agonal breathing has also been reported during electrical stunning of sheep and calves (Blackmore and Petersen 1981) As highlighted earlier, vocalisation must be used cautiously when assessing unconsciousness. Care must also be taken to differentiate vocalisation from other sounds the animal may make due to involuntary passage of air along the vocal cords or sounds from agonal breathing. Grandin (2013) noted that, whilst vocalisation may be related to social communication, it may also be an expression of pain when animals are exposed to a stimulus. For instance, the presence of vocalisation in an animal that has been subjected to stunning is an indication that that the animal is conscious; however, the absence of it should not be assumed (continued)

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Table 2.2 (continued) Behavioural indicator

Rhythmic breathing

Convulsions

Protruding tongue

Explanation to mean that it is unconscious. Grandin and Smith (2004), Grandin (2013) and Carlson (2007) reported that vocalisation in stunned animals is indicative of an ineffective stun, animals are likely to be in pain and distressed as a result, and such animals must be re-stunned immediately. Carlson (2007) explained that vocalisation is controlled by the frontal lobe and primary motor cortex which are associated with conscious perception When animals are stunned prior to slaughter, the return of rhythmic breathing is considered to be the first sign of possible recovery from unconsciousness (Anastasov and Wotton 2012). Mitchell and Berger (1975) explained that rhythmic breathing is an indication of the functioning of some parts of the spinal cord and the corticospinal tract. The corticospinal tract is a pathway of white matter which begins at the cerebral cortex and ends in the spinal cord (on the lower motor neurons). Therefore, the presence of rhythmic breathing in a stunned animal is likely to be associated with consciousness, and such animals should be re-stunned. It is worth reiterating that an animal that is breathing may (or may not) be conscious. Verhoeven et al. (2015) noted that a breathing animal may be unconscious but any animal that ceases to breathe is either dead or unconscious Convulsions are another behavioural indicator that must be interpreted with caution, because they can be observed in both conscious and unconscious animals. The difference between the two is that, whilst convulsions in conscious animals may be coordinated, convulsions in effectively stunned animals (unconscious animals) are usually uncoordinated limb movements. Post-stun convulsions can sometimes be misinterpreted as rhythmic breathing (Wotton and Sparrey 2002), a suggestion that animals may be regaining consciousness. Uncoordinated limb movement post-stun has been shown to occur during electrical stunning (Anastasov and Wotton 2012) and gas stunning (Marzin et al. 2008). During mechanical stunning, injuries to the brainstem essentially disconnect the brain from the body (specifically the spinal cord), resulting in post-stun convulsions. Poststun convulsions are therefore not brainstem reflexes, due to the absence of higher motor control, but spinal reflexes that are not consistent with consciousness (Lambooij 2004) An animal showing a protruding tongue after stunning may be unconscious, because it is not a normal behaviour in conscious animals. Although this is not a commonly used behavioural indicator in assessing unconsciousness, it has nonetheless been reported by several researchers. Grandin (2002) made a number of observations with animals showing protruding tongues after stunning and concluded that animals exhibiting this behaviour are likely to be unconscious. This behaviour is thought to be linked to the dysfunction (as a result of stunning) of cranial nerves controlled by the twelfth cranial nerve, the hypoglossal, which is responsible for controlling the extrinsic and intrinsic muscles of the tongue in conscious animals. Gregory et al. (2007) arrived at a slightly different conclusion; they explained that a protruding tongue observed immediately after captive bolt stunning does not necessarily indicate the depth of concussion. The authors (continued)

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Table 2.2 (continued) Behavioural indicator

Nystagmus

Relaxed jaw

Explanation further elaborated that protruding tongues observed after bleeding can be used as a behavioural indicator of unconsciousness. From the conclusions of Grandin (2002) and Gregory et al. (2007), it can be inferred that, whilst Grandin is conclusive about the use of protruding tongues as an indicator of unconsciousness after stunning, Gregory and colleagues were more cautious about its reliability Nystagmus is a condition which results in involuntary rhythmical, repetitive eye movements (that are usually horizontal, but can also occur vertically). It can be observed in conscious human subjects and is associated with poor coordination and imbalance, and thought to be caused by injury to the central nervous system. In human babies, it can be inherited or idiopathic (due to unknown causes) and is usually associated with developmental problems with the eyes or brain. From a pre-slaughter stunning perspective, Hüfner et al. (2007) reported that it is associated with damage to the cerebellum (presumably during mechanical stunning). When observed in stunned animals, it is recommended that animals must be re-stunned because it is indicative of a shallow depth of concussion and animals can quickly regain consciousness (Gregory et al. 2007). A number of studies have found animals exhibiting nystagmus during mechanical and electrical stunning (Bourguet et al. 2011; Gregory et al. 2007; Grandin 2002). However, Atkinson et al. (2012) reported that, during carbon dioxide stunning of pigs, there was no incident of nystagmus Jaw tension is controlled by the trigeminal nerve, the largest of the 12 cranial nerves. It transmits sensory information to the jaw and the skin around it and ensures that tension is maintained in fully conscious animals. Grandin (2002) reported that a relaxed jaw is indicative of an unconscious animal. When the cranial nerves become dysfunctional during stunning, the transmission of sensory information to the jaw ceases, resulting in its relaxation

with animals that are conscious but mentally inactive and frequencies above 12 Hz (β) are commonly recorded in subjects that are fully conscious and active. Seth et al. (2005) noted that, in conscious animals, in addition to high frequency (usually α and β), EEG recordings also show low amplitude waves. Conversely, the EEG pattern in unconscious animals is characterised by predominantly low frequency (i.e. δ and θ) and high amplitude. During the analysis of EEG recordings to evaluate electrical activity of the brain, EEG epoching is usually used to analyse the frequency, amplitude and power. This is a procedure used to divide the continuous EEG signal into time-specific events. Verhoeven et al. (2015) reported that, during stunning and slaughter, there are four distinguishable stages of EEG associated with different levels of consciousness; these states are explained in Table 2.4. The time to loss of consciousness after slaughter without stunning has been measured with EEG. Johnson et al. (2014) reported that sheep can remain sensible for 2–8 s after the neck cut, but it could also last for up to 20 s. Friedman et al. (2021)

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Table 2.3 Description of the reflexes that are relevant in the assessment of consciousness during slaughter Type of reflex Corneal reflex

Righting reflex

Palpebral reflex

Spinal reflex

Threat reflex

Pupillary light reflex

Description Dugdale (2010) explained that the corneal reflex is the involuntary blinking of the eyelids in response to a threat or stimulation in the cornea of the eye, and it is the last reflex that is lost in anaesthetised animals. When the cornea is touched in a conscious animal, information is transmitted to the brainstem that elicits an automatic response through the retraction the eyeball and closure of the eyelid. This is considered an important indicator in assessing unconsciousness in animals following stunning. The absence of a corneal reflex is associated with the incapacitation of part of or the whole of the reticular formation, which is an important indicator of loss of awareness (Sturges 2005; Laureys 2005). The presence of a corneal reflex may also be associated with residual brainstem activity, therefore this must always be used cautiously This describes the return of an animal into its normal upright position as a result of regaining consciousness and is sometimes referred to as the head righting reflex. During stunning of large ruminants in particular, loss of the righting reflex is an indication of the onset of unconsciousness This type of reflex elicits a similar response to the corneal reflex, also resulting in involuntary blinking, but it disappears more quickly in anaesthetised animals than the corneal reflex. It is associated with stimulating the medial canthus of the eye, as opposed to the cornea during the corneal reflex. The palpebral reflex and corneal reflex are, together, referred to as eye reflexes This category of reflexes may be employed to assess unconsciousness, depending on the type of spinal reflex and its function in pain perception. Verhoeven and others (2015) noted that spinal reflexes are categorised into flexor and stretch reflexes, and explained that stretch reflexes are involved in the control of posture whilst flexor reflexes are involved in nociception. For the purpose of assessing unconsciousness, the flexor reflex is the most important (Erasmus et al. 2010). When a painful stimulus is applied to an animal in the form of nose or ear prick, for instance, the flexor reflex elicits a painful withdrawal reflex as a consequence of the noxious stimulus Unconsciousness can also be assessed by mimicking a threat to the animal, which can be accomplished by attempting to touch the eye with an object (e.g. a finger or a pen). The involuntary blinking, closure of eyes or withdrawal of the animal’s head during a threat to the eye describes the threat reflex and may signify consciousness, whilst the absence of blinking or head withdrawal during a threat may be a sign of unconsciousness. Where there is physical destruction of the brain during stunning (e.g. penetrative captive bolt stunning or use of a shotgun), the presence of eye threat reflexes is likely to be indicative of ineffective stunning and animals may remain conscious. The reason for this is provided by Gregory and Shaw (2000), who explained that physical destruction of the brain causes brain trauma which should abolish cranial nerve reflexes. The presence of cranial nerve reflexes (e.g. eye reflexes) is therefore an indication of likely brainstem activity (which should normally be absent when animals are effectively stunned with a penetrative captive bolt which causes gross physical damage) and shows that animals are likely to be conscious Blackman and others (1986) reported that the pupillary light reflex, the involuntary attempt to adapt to the light stimulus when light is flashed on the eye of an animal, it is an important reflex used in assessing unconsciousness (continued)

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Table 2.3 (continued) Type of reflex

Pedal reflex

Description during exsanguination, because exsanguination impedes blood supply to the retina The pedal reflex relates to the withdrawal of the feet when the skin between the toes is exposed to a noxious stimulus in the form of pinching. This can be used to assess unconsciousness, but there are some issues with its practicality in commercial abattoirs. For instance, it is not a suitable method for assessing unconsciousness in ruminants and during the clonic phase of epilepsy (due to convulsions). It is suitable for use in poultry and is also used in small laboratory animals for assessing the depth of anaesthesia

Table 2.4 Time-specific events or different stages observed in EEG recording during stunning and slaughter Stage of EEG Active/fully conscious stage Transitional stage Unconscious stage Isoelectric (flat EEG) stage

Description Shows animals who are fully awake and records a high frequency and low amplitude on the EEG In this stage, the frequency decreases with increased amplitude, but the changes are not as pronounced as in the next stage This stage is characterised by pronounced increase in amplitude with decreased frequency • During this stage, the brain no longer functions, therefore no recording is usually captured on the EEG. This stage is not consistent with consciousness

assessed the time to loss of consciousness in 34 White Peckin ducks slaughtered without stunning, they found that the time to loss of consciousness ranged between 20 and 383 s. They identified the following as the factors affecting the time to loss of consciousness during slaughter without stunning; (1) The accuracy of the severance of blood vessels, (2) The incidence of clotting at the cut ends of the carotid arteries (particularly in cattle) and (3) Sharpness of the knife which can increase the number of cuts (particularly in cattle). Newhook and Blackmore (1982) investigated the time to loss of permanent sensibility in 16 mature sheep and five 1-week-old lambs using EEG epoching in three separate protocols. In the first experimental setup, they found that the time to loss of sensibility following slaughter without stunning was between 2 and 7 s in both sheep and lambs, and the isoelectric EEG point/stage was recorded to be between 10 and 43 s. In the second experiment, sheep were minimally anaesthetised before slaughter, and the isoelectric EEG in these animals was found to be between 18 and 70 s. The third experiment involved the slaughter of a single sheep by cutting one carotid artery and one jugular vein on one side of the neck. The EEG recording showed that the onset of insensibility was delayed for about 29 s. This is due to the fact that oxygenated blood continued to flow from the heart to the brain through the intact carotid artery on the opposite side of the neck, thereby keeping the animal sensible for a longer duration, when compared with the severing of both carotid arteries and jugular veins on both sides of the neck (2 to 7 s). In another experiment, Devine et al. (1986) investigated the effect of pre-slaughter

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electrical stunning and neck cutting (without stunning) of sheep and calves on the EEG. The time to loss of sensibility following neck cutting without stunning was slightly longer than that reported by Newhook and Blackmore (1982): it took sheep 8–22 s to lose sensibility, whilst calves took 79 s. The researchers also measured the duration of insensibility induced by head-only electrical stunning and found that high amplitude EEG waves were recorded immediately after stunning, lasting for 47 s and 33 s in sheep and calves, respectively. They concluded that the EEG recordings showed larger amplitude for animals that were electrically stunned than those slaughtered without stunning, and, in their opinion, EEG criteria for recording the sensibility of animals slaughtered without stunning should not be used for those electrically stunned prior to neck cutting. Aside from using EEG to estimate the time to loss of consciousness, Friedman et al. (2021) reported that some researchers have previously used loss of posture as an indicator of loss of consciousness during slaughter without stunning. Barnett et al. (2007) used the loss of posture technique and found that in broilers, the mean time was 14 s, with some broilers not losing posture for up to 26 s.

2.2.4.4 Changes in Blood Parameters Where the method of stunning requires the inhalation of gases, physiological changes in blood parameters can be used to assess unconsciousness. This method is therefore not suitable for assessing unconsciousness during electrical and mechanical stunning; however, it has been used in evaluating stress associated with pre-slaughter handling and slaughter without stunning (Nowak et al. 2007; Sabow et al. 2016). Nakyinsige et al. (2013) and Sabow et al. (2016) found high levels of creatine kinase and lactate dehydrogenase in blood samples obtained from rabbits transported under hot, humid tropical conditions and goats subjected to slaughter without stunning, respectively. According to Nakyinsige et al. (2013), high levels of creatine kinase (CK) and lactate dehydrogenase in serum are indicative of stress and muscle fatigue. In an experimental comparing the stress associated with group and individual restraint of sheep, Bates et al. (2014) analysed CK and cortisol levels in blood samples and reported that the two stress hormones were higher in sheep that were individually restrained in V-restrainers in comparison to those that were restrained in groups. Raj and Gregory (1996) noted that, during carbon dioxide gas stunning, unconsciousness is induced by hypercarbic hypoxia resulting in the depression of brain activity. The series of changes that occurs following the inhalation of carbon dioxide (and other gas mixtures) results in changes in pH, oxygen saturation, bicarbonate concentration, oxygen partial pressure and carbon dioxide partial pressure. With regard to the effect of carbon dioxide stunning on the pH of blood and other fluids, Gregory et al. (1987) reported that there is a reduction in the pH of cerebrospinal fluid, making it more acidic. Rodriguez et al. (2008) found that, when pigs were stunned with carbon dioxide, it led to a reduction in pH, oxygen saturation and oxygen partial pressure. However, there was an increase in carbon dioxide partial pressure and bicarbonate concentration.

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Assessment of Death

In addition to the assessment of unconsciousness during slaughter, EU animal welfare regulations (EC1099/2009) require verification of the absence of life before dressing animals or scalding poultry. This requirement is in place to eliminate any risks of animals recovering from consciousness on entering the scalding tank or while being dressed (a process that involves skin and offal removal). However, the diagnosis of death is not a straightforward procedure, particularly in commercial abattoirs. In humans, procedures for the diagnosis and confirmation of death vary from country to country and it remains a controversial issue from a cultural and religious perspective. While some countries diagnose death based on the permanent (irreversible) loss of function of the whole brain, others have chosen to base the diagnosis on the permanent loss of function of the brainstem. For instance, the diagnosis of death in the UK is based on irreversible loss of function of the brainstem, while diagnosis in the USA is based on the irreversible loss of function of the whole brain. In the UK, a series of tests must be conducted on brainstem function, as shown in Table 2.5. From a Halal slaughter perspective, the assessment of death prior to and post neck cutting is one of the most important requirements of Halal meat production. The animal needs to be alive prior to neck cutting in order to comply with the Halal rules, and assessment of death post neck cut is carried out simply for animal welfare reasons. Diagnosing death in animals under commercial conditions is not as straightforward as diagnosing death in humans. In an abattoir scenario, thousands of animals may be slaughtered within a short time, so there is not sufficient time for the death of each and every animal to be objectively diagnosed, particularly during the slaughter of poultry. Furthermore, objective assessment of death in an abattoir scenario during experimental investigations may be impeded by confounding factors in the abattoir, such as noise, which may lead to errors in recording devices such as EEG, brain tomography, and angiography. The cause of death in non-human animals is also likely to differ from that of human subjects. For instance, death in non-human animals in slaughterhouses is usually caused by the intentional deprivation of the brain of its nutrients (oxygenated blood) through exsanguination or the causation of injury (trauma) to vital structures in the brain using stunning techniques. The death

Table 2.5 A list of the series of confirmatory tests that must be conducted to assess the function of the brainstem during neurocentric diagnosis of death in human subjects in the UK (Adapted from The Academy of Medical Royal Colleges 2008) No pupillary response to light No corneal reflex No vestibule-ocular reflex (caloric test) No ocular-cephalic reflex (Doll’s eye) No motor response to pain—in the trigeminal nerve distribution No gag reflex in response to suction through endotracheal tube or tracheostomy Apnea persists despite a rise in PaCO2 to greater than 50 mmHg (6.6 kPa) against a background of a normal PaO2

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of non-human animals destined for the food chain is more often than not induced, while human death may occur naturally and without any physical damage to the brain. The duration and volume of blood loss may be used in abattoirs to estimate the time after which the animal will probably be dead. Some researchers have suggested that 4–5 min of complete brain ischaemia is sufficient to cause the death of animals due to the irreversible damage caused by the deficiency of oxygenated blood in the brain and other vital parts of the body (Allen and Buckberg 2012). In some species of animals, 4–5 min may not be sufficient to cause death, due to the anatomy of blood flow from the heart to the brain, especially if the neck cut is not properly performed. According to the French Public Health Code, Article R1232-1, errors in the diagnosis of death in humans can be eliminated by ensuring that any technique or method used should include an assessment of the absence of signs of life, taking into account the absence of consciousness, loss of all brainstem reflexes, absence of spontaneous breathing, absence of spontaneous motor activity and persistent respiratory and cardiac arrest. Confirmation of the absence of electrical activity in the brain, cessation of blood flow and metabolic activity may also be needed. While it is impractical and nearly impossible to conduct some of these assessments in abattoirs, it is important to have a mechanism of confirming death before animals are scalded (in the case of poultry) or dressed (in the case of mammals). In the case of poultry, thousands of birds are slaughtered with line speeds that do not permit proper assessment of death before they go through the scalding tank. The author of this book is aware of poultry abattoirs in the UK and within the EU that slaughter between 15,000 and 20,000 birds per hour. The sheer number of birds involved does not permit the assessment of death in every bird. The author has extensive experience of working with halal certification bodies in Europe and America, and he is aware of some Halal certification bodies who diagnose death based on the following criteria. However, the line speed in most commercial abattoirs will not permit these observations to be made on every animal (particularly in poultry abattoirs), so it is likely that some live birds may enter the scalding tank: • Absence of a beating heart. As highlighted earlier, some Islamic jurists define death based on the functioning of the heart. The presence of a beating heart denotes a live animal and vice versa. • Immobility/absence of convulsions. The cessation of post-neck cut convulsions or movement are used as signs of death. It must be noted that, prior to the advent of neuroscience, death was defined based on the absence of movement. • Completion of bleeding. Some Islamic scholars have overcautiously relied on the completion of bleeding as the point at which the animal is confirmed dead. From a Shariah and animal welfare standpoint, it is of grave concern that some animals or birds may be further processed while still alive. Halal certification bodies, Halal abattoir operators, animal welfare scientists and Islamic scholars need to work

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collaboratively to agree robust criteria for assessing death, to ensure that all animals are dead before processing commences.

2.3

Stunning of Animals

When applied correctly, stunning induces brain dysfunction, leading to the induction of unconsciousness. The original objective of mechanical stunning (particularly with the poleaxe) was to safeguard human safety and improve the efficiency of slaughter operations, rather than to improve animal welfare, as it is now. There are different techniques that can be employed to effectively stun animals, the choice of which largely depends on the species of animal and the objective of slaughter, i.e. conventional and religious rites: • Electrical stunning. Animals can be electrically stunned in different ways: headonly (mainly for small and large ruminants, poultry and pigs), head-to-body (mainly for small and large ruminants and pigs) and via a water bath (mainly for poultry). Proponents of Halal stunning generally accept only head-only electrical stunning. • Mechanical stunning. Animals can be stunned with mechanical devices by applying a concussive blow to the head to induce immediate loss of consciousness. This method of stunning is mainly used for large ruminants; however, small ruminants, poultry and pigs may be stunned with mechanical devices. • Controlled atmosphere (gas) stunning. In this method of stunning, animals are exposed to gaseous mixtures to induce loss of consciousness. The induction of unconsciousness is not immediate.

2.3.1

Commercially Available Stunning Methods

Annex 1 of the European Council Regulation, EC1099/2009 outlines acceptable stunning and/or killing methods that can be used during slaughter, disease control, culling of unwanted sexes of animals and killing under various situations. The methods are categorised into mechanical, electrical, gas and ‘other’ methods (see Table 4.2 in Chap. 4, adapted from European Council Regulation, EC1099, 2009, that outlines the suitability of each stunning technique for different species of animals and the processes that should be used). This section of the book seeks to explore the mechanisms and principles of the main methods of stunning currently used globally for the humane slaughter of different species of animals: electrical, mechanical and gas.

2.3.1.1 Mechanical Stunning A number of mechanical stunning techniques are listed in Annex 1 of EC1099/2009 as acceptable means of humanely dispatching animals. During the slaughter of animals for human consumption, the two commonly used mechanical stunning

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Fig. 2.4 Different variants of mechanical stunning devices that can be used to slaughter animals, but do not necessarily comply with the Halal rules (Images adapted from www.qcsupply.com)

devices are penetrative and non-penetrative captive bolt guns. It is contrary to EU legislative requirements to use a non-penetrative captive bolt on ruminants that weigh more than 10 kg. As a result of this requirement, non-penetrative captive bolts are generally used on kid goats, sheep and pigs within the EU. The situation is different in some parts of the world, where the technique is approved for all animals irrespective of the weight; for instance, in Australia, New Zealand and the USA, there are no restrictions on its use. The mechanism of induction of unconsciousness is similar during the application of all the mechanical stunning/killing techniques, with the exception of a few (for instance, maceration and cervical dislocation). Figure 2.4 shows different mechanical stunning devices used for penetrative captive bolt stunning, non-penetrative captive bolt stunning, free projectiles shot from firearms and a percussive blow to the head as well as (not pictured) maceration and cervical dislocation. When choosing a killing or mechanical stunning technique,

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a number of factors must be taken into consideration in order to inform the choice of a suitable method: • What is the purpose of the killing? Is it for disease control, slaughter for human consumption, culling, experimentation, etc.? • What species of animals are involved? Are they ruminants, monogastric, poultry or other species of animals? • How old is the animal and how much does it weigh? Some mechanical killing techniques (e.g. cervical dislocation, maceration, percussive blow to the head) are age or weight restricted. • What is the target market? Is it for conventional meat production or meat for consumption by people of faith? 2.3.1.1.1 Mechanism of Induction of Unconsciousness During mechanical stunning, unconsciousness is generally achieved by a blow to the head that transfers kinetic energy from a mechanical device (e.g. a captive bolt gun) to the head, resulting in differential movement of the skull and the brain. The device may be designed with a metallic rod which penetrates the skull; the induction of unconsciousness is, however, not dependent on whether the skull is penetrated or not. The reason for penetrating the skull is to cause sufficient gross physical damage to the brain to prevent recovery from unconsciousness. The non-penetrating captive bolt is designed with a blunt (mushroom shaped) end that does not penetrate the skull but may cause an indentation or a skull fracture. Figure 2.5 shows varying degrees of damage caused by the impact of non-penetrative captive bolts on the skull, while Fig. 2.6 shows the level of damage to the brain sustained when cattle were stunned with penetrative and non-penetrative captive bolt guns. Terlouw et al. (2016a) explained that the penetrating bolt causes sufficient physical destruction of parts of the brain that are involved in controlling wakefulness. According to Blackmore (1979) and Finnie (2001), it is the reticular formation and the ascending reticular activating system that need to be damaged during penetrative captive bolt stunning. The effectiveness of the mechanical stun is influenced by bolt velocity and mass, represented by the kinetic energy equation: KE = ½ mv2 where KE = Kinetic energy, m = bolt mass and v = bolt velocity. From the kinetic energy equation, KE is directly proportional to both the mass and velocity (squared), the mass describes the quantity of matter in the bolt (usually in kilograms or grams) and the velocity describes the rate of change of position, i.e. a vector quantity. To better understand the mode of operation of mechanical stunners, one may assume velocity and speed to be the same, but it is useful to reiterate that, whilst speed does not have a direction (scalar quantity), velocity is directional (vector quantity), so velocity can be understood as speed with a direction. Mass and weight are similar but different: both are measured in kilograms or grams; however, mass remains constant whereas weight changes with changes in gravity.

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Fig. 2.5 Varying levels of indentation and damage to the skull caused by non-penetrative captive bolt stunning of adult cattle. These skulls were inspected by the author of this book as part of an audit on behalf of one of the Halal certification bodies in the UK. The plant in question is in Ireland

Fig. 2.6 The level of damage caused by a non-penetrative captive bolt (left) and a penetrative captive bolt gun (right). During both methods of stunning, some level of damage is done to structures of the brain. Recovery is prevented during penetrative captive bolt stunning due to the penetration of the bolt through the skull to destroy the brain

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As explained earlier, during mechanical stunning, a mechanical device is used to apply a blow to the head. The impact transfers kinetic energy to the head in the form of a shock wave, and this creates a pressure gradient that leads to the movement of the brain (from its normal position) away from the skull, causing concussion. The shock waves also cause lesions and damage to brain tissues, leading to disturbance in normal blood flow within the brain (Posner et al. 2008). This deprives important brain structures of their necessary blood supply, leading to parts of the brain becoming dysfunctional. Terlouw et al. (2016a) explained the impact of concussion on intercellular ion content, reporting that concussion during captive bolt stunning induces potassium ion efflux and calcium ion influx from cell membranes, which result in the depolarisation of brain cells of the cerebral hemisphere. Posner et al. (2008) explained that mechanical stunning disrupts the function of the mitochondria by releasing excitatory neurotransmitters (see Table 2.1 for a list of excitatory neurotransmitters and their functions) into the mitochondria, which leads to the production of energy, resulting in disruption of the normal functioning of neurons, inducing unconsciousness. It is important to note that, whether animals are stunned with penetrative or non-penetrative captive bolts, there is some level of damage to the brain, which leads to haemorrhaging (see Fig. 2.6). Non-penetrative captive bolt stunning can lead to an indentation or crack in the skull (see Fig. 2.5). This is important from a Halal meat production perspective because some Muslim authorities (e.g. in Malaysia) approve non-penetrative captive bolt stunning on condition that it does not crack the skull. Others have taken a more cautious approach and do not approve any form of mechanical stunning, due to the uncertainties surrounding its reversibility.

2.3.1.2 Electrical Stunning Electrical stunning involves the placement of electrodes (usually on the head of the animal, but they can also be applied to other body parts) to deliver optimal voltage, with the aim of delivering sufficient voltage to the brain in order to induce unconsciousness. The proportion of the applied voltage that reaches the brain induces brain dysfunction to cause immediate loss of consciousness. During his PhD at Bristol University, the author of this book investigated the application of electric current to the heads of cattle that were slaughtered in the University’s abattoir (Fuseini 2019b). During the experiment, the author confirmed that the application of voltage to cattle heads via neck and nose electrodes was the best route of application of voltage to cattle heads. Application of voltage through the top of the head is impeded by the skull. With this information, the author, with the support of his supervisors, successfully developed a prototype electrical stunner which is currently undergoing efficacy testing. At present, the majority of Halal certifiers do not approve the commercially available beef stunning methods for Halal meat production (e.g. captive bolt stunning and electric head-to-body stunning). The new system is likely to appeal to opponents of current stunning methods that are deemed inconsistent with Halal slaughter. Figure 2.7 is the experimental setup of the in vitro experiment with cattle heads. Using Ohm’s Law:

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Fig. 2.7 The application of voltage to a cow’s head with a view to measuring the voltage across the head (and brain). A1 is the distance between two brain electrodes and the electrodes were inserted into the brain to measure the amount of voltage that reached the brain. This was an experimental setup as part of the author’s PhD research to evaluate the efficacy of applying voltage via nose and neck electrodes, as part of the development of a new system of head-only electrical stunning (Adapted from Fuseini 2019b)

V = IR where V = voltage, I = current and R = resistance/impedance, the resistance of the cow’s head was calculated. Furthermore, with knowledge of the voltage in the head and brain, as well as the distance between the electrodes, the electric fields in the head and brain were calculated. Terlouw et al. (2016a) reported that, if applied correctly, the amount of current applied to the head should be the same as the amount of current that reach the brain. However, Fuseini (2019b) found that there were variations between the amounts of applied currents and those measured in the brain. This may be due to the fact that the cattle heads behaved differently during the experiment, compared to the heads of live animals. Another reason for the difference may be due to the nature of contact between the neck and nose electrodes. According to Lee and colleagues (2012), the electric field established in the brain has a direct impact on depolarising neural membranes in a synchronised fashion, resulting in the induction of epileptic seizures in the brain. The depolarisation of neurons and subsequent induction of seizures disrupts the equilibrium of neurotransmission as a result of increased release of neurotransmitters (e.g. GABA), changes in blood flow, changes in oxygen requirements and the acidification of the brain as a consequence of the production of lactic acid (Ingvar 1986; Enev et al. 2007; Posner et al. 2008). The nature and duration of unconsciousness is dependent on the structures of the brain affected by the seizures. According to Terlouw et al.

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(2016a) and Blumenfeld and Taylor (2003), unconsciousness may be short- or longlasting. Where the seizures involve subcortical structures, generalised seizures ensue, resulting in profound or long-lasting duration of unconsciousness (Blumenfeld and Taylor 2003). Cook et al. (1995) measured the release of neurotransmitters during electrical stunning of sheep using 1 Ampere of current at 50 Hz applied for 0.1 to 20 s. They concluded that electrical stunning of sheep with 1 Amp, 50 Hz, 500 V applied for less than 0.2 s did not result in effective stunning. Furthermore, the level of excitatory neurotransmitters (aspartate and glutamate) was similar to the level of the amino acids released during arousal. When the voltage was applied for over 0.2 s, they successfully recorded epilepsy in the EEG, and the levels of aspartate and glutamate were significantly higher than when voltage was applied for less than 0.2 s. The authors concluded that the application of voltage for 4 s was probably the best duration for effective electrical stunning in sheep, inducing sustained duration of epilepsy and increased levels of excitatory and inhibitory amino acids in the brain. When animals are effectively stunned to induce unconsciousness, cortical structures (limbic and somatosensory) become dysfunctional, and this results in the absence of the ability of animals to perceive pain. Electrical stunning may be applied as a head-only stunning or head-to-body stunning. As the name suggests, head-only is where voltage is aimed at the head to disrupt brain function without affecting normal cardiac rhythm. Head-to-body stunning, on the other hand, involves the application of voltage to the head, followed immediately by the application of a second voltage to fibrillate the heart (i.e. induce cardiac arrest). During head-to-body electrical stunning, electrodes are placed on the head (to stun) and the back, brisket or sternum (to fibrillate the heart), depending on the species of animals. Wotton and colleagues (2000) described the mode of application of current in electrical head-to-body stunning of cattle using the Jarvis Beef Stunner. It is important to point out that there are two types of Jarvis Beef Stunners; the type used in the EU has a cardiac arrest cycle (head-to-body electrical stunning) while the second type is a head-only Jarvis Beef Stunner mainly used in New Zealand. Wotton and colleagues (2000) explained that during the use of headto-body Jarvis Beef stunning, electrical current is applied in three sequential cycles: • The first cycle involves the application of current for 3 s to disrupt brain function and induce unconsciousness. • The second cycle involves the application of current to the brisket for 15 s in order to induce ventricular fibrillation (or cardiac arrest). • The third cycle involves a 4 s application of current to incapacitate the spinal cord, with the aim of reducing post-stun convulsions. Due to the cardiac arrest cycle, many Muslims do not approve this method of stunning because it causes the death of cattle before the Halal cut. The Jarvis Beef Stunner was first developed in New Zealand, mainly for Halal meat production. It was developed without the cardiac arrest cycle in order to cater for the Halal market. However, low voltage post-stun electro-immobilisation is used to manage post-stun convulsions to protect operator safety.

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Electrical water bath stunning is the commonest stunning method used for Halal poultry meat production. In the case of non-Halal poultry meat production, controlled atmosphere stunning is the main method. Although many regard it as a headonly electrical stunning, the mode of application of current involves the inversion of birds into an electrified water bath where current is passed from the head, through the body, to the feet. It is therefore, arguably, not a head-only stunning method and, in some cases, it can induce cardiac fibrillation which can lead to the death of birds. It is against this backdrop that some Muslim authorities do not approve it as a Halalcompatible method of stunning. The author of this book and his colleagues recently published a scientific paper highlighting the welfare aspects of water bath stunning and why it may not fully comply with Halal slaughter (Fuseini et al. 2019). Birds must be inverted and shackled prior to immersion into the water bath, and it is the inversion and shackling of birds that poses significant welfare concerns. There are also issues with pre-stun shocks and some birds receiving insufficient current, leading to ineffective stunning. Figure 2.8 shows an inverted and shackled bird prior to entry into the water bath. European Council Regulation, EC1099/2009 outlines the electrical parameters that should be used during electrical stunning (see Tables 2.6 and 2.7).

2.3.1.3 Controlled Atmosphere (Gas) Stunning The use of gases or gaseous mixtures to stun animals is common in the industrialised world, but it is not generally approved for Halal and Shechita slaughter. Gas stunning is sometimes referred to as controlled atmosphere stunning (CAS). Within the EU and other parts of the developed world, CAS is commonly used during the slaughter of pigs and poultry; in fact, it is the main method of stunning for poultry meat production in the UK. According to data from the UK’s Food Standards Agency, 70% of broiler chickens and over 90% of spent hens were stunned using carbon dioxide and other gaseous mixtures in 2018 (FSA 2018). The CAS method has some animal welfare advantages, compared to water bath stunning, as detailed below: • Gas stunning reduces handling. Birds are usually stunned without being removed from transport crates. • Gas stunning eliminates inversion and shackling of birds, thereby reducing stress and injuries. • Gas stunning eliminates pre-stun shocks associated with water bath stunning. • The effectiveness of gas stunning is independent of the electrical resistance of birds, and it therefore eliminates ineffective stunning associated with water bath stunning of birds with higher resistance. Birds’ resistance is influenced by the nature of their tissue, bone, muscle, skin and scales on their feet. Despite the numerous welfare advantages of gas stunning, the major Halal importing countries (for instance, the UAE, Saudi Arabia, Kuwait, Malaysia, Turkey and Qatar) do not approve of its use for Halal meat production. This is mainly because gas stunning is a killing method, and the majority of birds die when exposed

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Fig. 2.8 The inversion and shackling of chicken prior to water bath stunning; this method of restraint is also common during slaughter without stunning (Photo credit: University of Bristol) Table 2.6 Permitted minimum currents for head-only electrical stunning of different species of animals within the EU Animal type Bovine (i.e. cattle, less than 6 months of age) Bovine (i.e. cattle, 6 months of age and above) Ovine (i.e. sheep) and caprine (i.e. goats) Porcine (i.e. pigs) Chickens Turkeys

Minimum amount of current required 1.25 A 1.28 A 1.00 A 1.30 A 240 mA 400 mA

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Table 2.7 Permitted average electrical stunning parameters for water bath stunning of poultry in the EU (adapted from European Council Regulation, EC1099/2009) Frequency Das Recht der Tiere und Landwirtschaft