Animal Welfare. John Webster

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      The second approach is to present animals with a set of questions relating to their perceived needs and measure their responses. This is the science of motivation analysis (16). The simplest version of this approach is the Preference Test. In a typical experiment, the animal is given a choice, e.g. between two foods or two environments and invited to demonstrate a preference. The choice may be between options that we guess might create more or less satisfaction (e.g. two types of bedding material for pigs), or between options that may be more or less aversive (e.g. barren vs. enriched cages for hens). One classic approach is to place the animal in a T maze that allows it to choose between the two options of taking the path to the right or the left. This can tell us quite a lot. Pet food manufacturers may discover flavours preferred by cats (although cats are fickle creatures). Designers of enriched environments for intensively reared pigs or chickens can get some idea of the fixtures and fittings that these animals appear to favour or avoid. However, preference tests can sometimes reveal evidence to indicate that the scientist and the experimental animals are not thinking the same way. In one such experiment, mice were asked to choose between two environments deemed by the scientist to be more or less enriched by traversing a narrow tunnel between the two. Most mice chose to spend the majority of time in the tunnel. For them, this was better than either of the choices on offer (66). The scientists had assumed the mice would choose on the basis of comfort, whereas, in their minds, we must assume that the primary need was for a sense of security. The scientists posed a specific question to these mice and got an unexpected answer. It was the wrong question, but they had a better understanding of mice as a result.

      The main limitation of the preference test is that it makes no distinction between choices that are trivial and those that really matter. A more advanced approach to motivation analysis is to measure the strength of motivation by how hard an animal is prepared to work to get a reward in the form of a pleasant experience such as food, or relief from an unpleasant experience such as cold, pain, isolation, or a barren environment (16,45). Examples of the currency used to measure cost include the number of times the animal has to press a lever, or the amount of pressure it has to exert on a gate to obtain the reward. Specific rewards are ranked as more or less price elastic or price inelastic. Most animals, unless satiated, will continue to work for a food reward as the price is increased, which makes it price inelastic. The marginal reward of a different lying surface, e.g. straw vs. wood shavings may be price elastic: i.e. not worth too much effort. While the preference test can do no more than establish behavioural priorities, motivation analysis can determine how much these things matter.

The aim of motivation analysis is to devise tests that enable an animal (e.g. a rat or chicken) to demonstrate, by way of its actions, how it feels about the challenge with which it is faced, positive, negative, or indifferent. Having demonstrated that the test animal is motivated to act to receive a specific reward such as food or avoid a potentially unpleasant experience such as isolation or confinement, the scientist then measures the price the animal is prepared to pay to improve its welfare. They observe this behaviour, review the results in the light of current understanding as already described in the scientific ‘literature’ and form conclusions based on evidence as to the preferences and strength of motivation of the animal. This will be set out for publication in words, tables and diagrams. The scientist has used the medium of language to describe conclusions and decisions that arose first in the mind of the rat or chicken in order that other humans might better understand how it feels to be that chicken. This is reverse anthropomorphism, pure and simple.

      There is another profound conclusion to be drawn from studies such as these; one that is key to our understanding of the minds of our fellow mortals. Presented with a specific question, which can be quite complex, the rat or chicken has analysed the problem, worked out a satisfactory response and memorised the actions necessary to achieve that response without recourse to the uniquely human medium of the spoken and written language. Moreover, as we shall see later, the ability to solve simple problems set by scientists in the laboratory can be a very limited measure of an animal’s mental capacity. It pales into insignificance when set, for example, alongside the detailed large‐scale maps that a pigeon needs to carry in its head if it is to navigate its way home. Animals with sentient minds have the ability to acquire and retain a great deal of knowledge and understanding without the need for language as we understand it nor reference to external banks of information stored in libraries and/or Google. What is more, these animals may be able to convey this understanding to their offspring, i.e. to engage in the process of education. We are only just beginning to understand the capacity of non‐human animals to develop thought without language and convey these thoughts to others, but it is an ability worthy of the greatest respect.

Rules of Engagement

      Two main themes run throughout this exploration of the minds of sentient animals.

      Theme 1: The needs of a sentient animal are defined entirely by its own physical and emotional phenotype, its environment and its education, and these are independent of our own definition of the animals as:

       Wild: subsets, game, (e.g. fox) vermin (rat), protected (badger)

       Domestic: subsets, pet (dog), farm (pig), sport (horse)

In ‘A Cool Eye towards Eden’ I illustrated this theme with a picture of a brown rat in a larder. (Figure 1.1). I wrote at the time: ‘A normal reaction to the brief glimpse of a rat in one’s larder would be horror or, at least, a cold resolve to destroy the rat as quickly as possible, together with any others who happen to be around. Now study the picture more carefully. The rat is not only sleek to the point of being chubby but completely unalarmed by the flash photography, totally at ease in human company and altogether charming. Her name is Cordelia’. Once we give the rat a name we provoke a shift in attitude. Nevertheless, Cordelia was a rat, and a rat is a rat, whether we classify it as laboratory animal, vermin or pet. She adapted wonderfully well to an enriched environment with loving human contact (my adult daughter, also an academic). If she had grown up in the company of other rats in the wild, she would have adapted equally well to that and, in the interests of her own survival, become fearful and dangerous in the presence of humans. If she had spent most of her life isolated in a barren laboratory cage, she would have had limited opportunity to develop her mind through lack of experience and thus be unable to handle complex decisions such as how to reconcile fear and curiosity in the presence of a novel stimulus. However, the essence of the rat mind is the same, whatever its circumstances. We have no right to assume that some rats are more equal than others. The behavioural and emotional needs of any sentient animal are determined by its own sentience, and these are entirely independent of our perception of its lovability, palatability, utility or nuisance value. In the case of wild animals, be they rats, badgers or, indeed, elephants, there are valid reasons ranging from human health to sustainable management of habitat to operate a form of population control. However, the principle of respect for all life directs that this should be as humane as possible. Where there is no clear need for population control, the policy for wild animals should be to leave them well and leave them alone. The most humane approach to the sensitive and sustainable management of wild animals is to preserve their natural habitat and stay out of their way.

      Theme 2: It is an anthropocentric fallacy to assume that the greater the similarity of an animal species to the human species, the more intelligent they are and the more worthy they are of our concern and respect.

It is in our human nature to express most concern for the animals that look and appear to behave most like us. We are conditioned to believe that humans are the most intelligent of the animal species, so assume that animals that evolved in ways most similar to us must rank second. Thus, СКАЧАТЬ