Asking Animals: An Introduction to Animal Behaviour Testing

Birte L Nielsen

• Éditeur: CAB International
• Année: 2020
• ISBN:
  9781789240634
• Sujet: Medicine
• Sous-sujet: Veterinary Medicine

Contemporary, thought-provoking yet utterly practical, this book provides an introductory text covering the use and misuse of behaviour tests applied to animals. By including illustrative examples from a variety of species, the book inspires the animal scientist to think about what a given behavioural test can be used for and how the results can be interpreted. This text includes: the dos and don'ts of running behaviour tests and interpreting the results; many clear, simple illustrations which make the information readily accessible, down to earth, practical advice yet a thorough, evidence-based approach; information on behaviour tests for a whole range of species from companion, farm, zoo, laboratory and wild animals; succinct yet comprehensive text, designed to be read cover to cover and stimulate further reading. This book is an essential item in the researcher's toolkit when embarking on and devising any animal behaviour test and is valuable to students, established researchers, teachers and practitioners of applied ethology, animal welfare science, and veterinary science.

Five Things This Book is Not 1

You may have looked at your dog, horse or goldfish, and wondered what they were thinking. Does Rover like his new dog-house? Is my pony feeling cold in this weather? Wouldn’t it be nice if we could just ask them? Well, as the title of this book indicates, we can. The concept of using well-designed behavioural tests of animals as a way of asking them questions has been known about and used for a long time. Initially, behavioural tests were mainly carried out on laboratory rodents. Konrad Lorenz’s demonstrations of imprinting in greylag geese in the 1930s were a form of behavioural testing, but it wasn’t until later that domestic livestock species were included: Hughes and Black (1973) and Dawkins (1977) were among the first to apply behavioural tests to farm animals, in their case the domestic hen, by studying the responses of the birds in behavioural tests of preference for cage size and floor type. Since then, a plethora of tests have been developed to ask animals questions by monitoring their behaviour in different situations.

The subject of behavioural testing of animals is complex, rich and potentially controversial (see Chapter 12). And in an era where almost everything can be found online, do we really need another book on this subject? Yes, because many of the existing books are quite specialized in their approach or do not give much practical advice. These books, together with those on animal behaviour in general in which various behavioural tests are inevitably mentioned, tend to be focused on specific groupings of animals. This includes laboratory rodents and primates (Whishaw and Kolb, 2005; Crawley, 2007; Buccafusco, 2009), domestic animals (Fraser, 2010; Broom and Fraser, 2015; Jensen, 2017; Appleby et al., 2018) or wildlife species (Manning and Dawkins, 2012). These textbooks rarely dwell on the experimental test design, and – because it is not the purpose of these books – do not always consider the pros and cons of a given testing paradigm.

Having worked for most of my career in applied ethology of farm animal species and their welfare, I have also spent 9 years in a neuroscience research unit, carrying out behavioural experiments on olfactory responses of rodents, mainly rats. This has provided me with the privilege of seeing two very different sides of animal behaviour testing, and made me realize how rarely methods and behavioural knowledge are transferred between scientific disciplines. This book is an attempt to start bridging that gap.

Before you delve into the different chapters of this book, here is some important information to prevent confusion and disappointment, and to put you in the right frame of mind to make the most of the next 170 pages. You should be aware of the following:

This Book is Not Complete

It almost goes without saying that this book is but a snapshot of some of the tests developed to study animal behaviour. Each chapter heading could be a book in itself, and not all behavioural tests are included, nor are they described in depth. Space restriction is among the reasons why the book is not even trying to be more exhaustive. In order to have enough space to include a broad variety of behavioural tests, it has been necessary to exclude some tests to allow a more in-depth description and discussion of others. As happened to me when researching this book, this is likely to introduce you to test types or formats that you have not come across before. This, in turn, may provide new inspiration for your own scientific work, not only as a student but perhaps also as an experienced silverback in applied ethology. If you want to know more about specific tests, there are other more dedicated textbooks (e.g. Lehner, 1998; Wyatt, 2014). There are also fascinating articles describing how knowledge is obtained from animal research in terms of reproducibility of results and the limitations of our chosen model (e.g. Garner et al., 2017). Finally, Bueno-Guerra and Amici (2018) cover field and laboratory methods in animal cognition of more exotic species, including tortoises, sharks and bats.

This Book is Not Representative

Unlike a review article, the chapters are telling a story about different types of tests, and yes, cherry-picking has occurred. This has been done intentionally to introduce the reader to some of the more interesting examples of animal behaviour testing within each category. The book also does not give the history of animal behaviour testing, nor the origin of most of the tests mentioned, as many tests have already been refined and further developed since their first use. Descriptions of earlier incarnations of a given behavioural test are therefore only included if they are relevant for the understanding of the tests in question. Having worked for many years in olfaction, this sensory modality tends to crop up more often than it should by chance in this book, and I apologize in advance for this slight selection bias. However, if it piques your interest in the importance of olfaction for animal behaviour and welfare, I can (humbly) recommend a book written by distinguished colleagues in the field and edited by me (Nielsen, 2017).

This Book is Not About One Scientific Discipline

Although the main scientific discipline of animal behaviour testing is applied ethology, the subject does embrace a number of scientific disciplines, such as neuroscience, behavioural ecology and animal behaviour science in general, as well as genetics and nutrition, just to mention a few. This has also made it possible to cover a wide range of species (but see below), and I have found myself marvelling at tests done in animal models largely unknown to me, such as zebrafish and chimpanzees. I hope that by including examples from species not usually seen in the neuroscience or pharmacological labs, such as dairy goats and laying hens, this book can evoke the same sense of discovery that I experienced when researching it. The importance of this is more wide-ranging: when reading about the same type of behavioural test carried out, say, in mice by neuroscientists and in piglets by animal welfare scientists, it becomes clear that the approach to the test is very different. This is perhaps not surprising, because the goals of the study, and the scientific questions asked, are very different. It is, however, something we should all be aware of when using results arising from different scientific studies and disciplines.

This Book is Not About Insects

Apologies to all the insect aficionados out there, but there is a – hopefully good – reason to exclude them: I wanted to put the emphasis on sentient species and animals managed by humans, especially those covered by legislation on the use of animals for scientific purposes, such as the EU Directive (2010). The main species you will come across in the following chapters are therefore vertebrates. However, I cannot exclude the possibility that a single bee trial may have sneaked in without my noticing. If you are interested in insects, and specifically the neuroscience aspects of their behaviour, you may find the book by Menini (2009) of interest.

This Book is Not About Statistics

It would have been relevant and useful to have a section on statistical analysis of results from various behaviour tests and how to interpret the statistical results correctly. Researchers are sometimes unclear about what the replicate in their study is (e.g. individual or group), and what to do if the residuals of their analyses are not normally distributed. But, alas, I am no statistician. It is, nevertheless, an extremely important aspect of animal behaviour testing, and assistance should be sought from statistical experts in the field (Kaps and Lamberson, 2017). The first place to look for guidance in this specific area of biology is Martin and Bateson (2007), a text book that focuses on statistical issues when analysing behavioural data. In Chapter 11, different test considerations to take into account (or at least be aware of) are discussed, as a lot of statistical grief can be prevented by careful planning.

So the structure of this book is as follows: In the first chapters, I try to set the scene, describing how non-test observations provide information that is often the basis on which many behavioural tests rest. This leads on to a chapter on how to choose a test, both in theory but also very much in terms of practical considerations. The core of the book, Chapters 4–10, covers the main types of behavioural testing themes, such as tests characterizing an individual, standard tests of treatment effects, choice and preference tests, and ways to assess learning ability, as well as genetic aspects of behaviour. Each chapter covers only some of the available tests within each theme, and for each test type, I have chosen one or two examples from the current literature to illustrate the practical use of the test in question (Fig. 1.1). These examples are meant to demonstrate the breadth as well as the limitations of the tests, while covering a variety of species. The examples are often also included because they were the most interesting and fun to read.

Fig. 1.1. Each core chapter is based on a few select examples of the practical use of a limited set of tests within the chapter topic. These test examples have been chosen so as to cover a variety of vertebrate species across the whole book, as well as to highlight specific details in the tests and methods used.

I only have to glance at all the half-read … aargh, who am I kidding? – unread textbooks on my shelves to realize that although we may have the best intentions to read up on, say, the behaviour of cattle or the neurobiology of olfaction, when push comes to shove, there are only so many hours in the day. Most people working in science are already struggling to keep up-to-date with the scientific papers in their subject area. How should they find the time to read whole books, in particular one that deals with more methodological aspects and spans several scientific disciplines? The only chance that anybody (other than the technical editor) will read this book, is if I make it as easy to read as possible. I have therefore endeavoured to the best of my ability to write a relatively short book, which includes the more interesting examples of animal behaviour testing, written in language that is easily digestible and printed in a format that can be read while ...