VN October 2021

Vetnews | October 2021 11 No single definition for the term ‘animal welfare’ exists. Animal welfare science is a rapidly developing multidisciplinary field. It forms the research basis which grounds animal welfare protection for vertebrates (and a growing list of invertebrates). However, the fundamental principle of all animal welfare is that animals with a central nervous system are sentient and have cognitive abilities. Sentience relates to the ability to experience 1 : • Negative states o Pain o Hunger o Fear o Boredom, and • Positive states o Pleasure o Play o Contentment o Expectation Any human who works closely with animals knows and accepts this to some degree. Animal sentience is easily observed through the interpretation of animal behaviour and communication. However, the science of animal welfare has objectively proven that animals have the cognitive ability to think and experience positive and negative states. The animal welfare field is rapidly evolving. The concept of ‘animal welfare’ extends beyond just good physical health 2 . That is the adage of the ‘5 Freedoms’ (the concept of Freedom from pain, injury and disease dates back to the 1960s). Modern animal welfare embraces the fact that welfare needs to be assessed by whether the animals have good physical, as well as psychological, health. This gets confusing because humans then enter the realmof subjective experiences of non-human animals 2 . It is impossible to measure subjective experiences, yet the promotion of positive emotional and physical states can be measured through many different means e.g., anatomical, behavioural and physiological parameters 1,3 . The concept of animal sentience has evolved from the 1600s, when Descartes, a famous philosopher and mathematician, described animals as “automata”, incapable of feeling pain or suffering 4 . Animal sentience is essentially the realisation and acceptance by society and by the powers that be that animals are not ‘dumb’ creatures, functioning automatically by unreasoned instinctive reactions. Animals have highly developed nervous systems, giving them extraordinary species-specific cognitive adaptations to feel sensations and experience emotions similar to those experienced by human beings. As discussed above, these emotions may be positive and enjoyable, or negative and unpleasant, therefore causing animals stress and driving them into states of distress. There is a global undertaking to improve the welfare of animals based on fulfilling their needs to have a life worth living rather as opposed to mere existence under miserable conditions for human economic benefit, excitement and pleasure. In her 2012 review of animal sentience, Proctor stated that “demonstrating what animals are capable of is key to achieving a positive change in attitudes and actions towards animals and a real sustainable difference for animal welfare” 4 . Since then, the emergence of demonstrable animal sentience (even including insect sentience) has given rise to a drive for new and inclusive ethics for them when they are being used in scientific studies 5,6 . One of the most challenging aspects of understanding sentience in animals is proving its existence at a scientific level. Scientific approaches comprise testing animal behaviour in studies that give animals choices to which they respond. In other words, to use animal preference, motivation and aversion reactions in studies to ask questions about their emotional states, and particularly about the capacity to feel pain. With the increasing scientific knowledge on animal sentience, there is a greater understanding of the impact of humans on animals. Humans have moral and ethical obligations towards other individuals. This includes individuals of other species. If we house or otherwise interact with non-human animals, then we have an obligation towards safeguarding and promoting their welfare 7 . It is increasingly irrational and unethical to continue to cause harm to animals, intentional or otherwise, when this could be prevented by an appreciation of animal sentience and the changing human attitudes. This realisation has increased the protection of the welfare of vertebrate animals throughout the European Union (EU). Animal Sentience and its role in AnimalWelfare >>> 10