Animal sentience is the capacity of an animal to experience different feelings such as suffering or pleasure. Negative feelings or emotions include pain, fear, boredom and frustration, whilst positive emotions include contentment and joy. Sentience also extends to an animal’s ability to learn from experience and other animals, assess risks and benefits and make choices. These abilities rely upon animals being aware of changes happening around them (also known as perception) and being able to remember, process and assess information to meet their needs (also known as cognition).
It is generally accepted that humans are sentient but over time there has been a shift in acknowledging that other animals are also capable of experiencing different emotions. This was first recognised in vertebrate animals with recent scientific evidence that some invertebrates are also sentient. Animal sentience was first recognised centuries ago but has only in the last few decades been explored scientifically and included in animal related policies. In 2008, the signing of the Treaty of Lisbon officially acknowledged animals as sentient requiring full regard to their welfare requirements in the European Union. In 2017, the Victorian Government published the Animal Welfare Action Plan, which acknowledges animals as sentient. New Zealand, Canada, and the Australian Capital Territory also recognise sentience in legislation. When considering animal welfare, it is understood that the word ‘animal’ refers to sentient animals.
Understanding and recognising animal sentience is important to help identify the needs of animals and to assess their welfare in different circumstances. For example, animals farmed for food under intensive or free-range systems, animals in zoos and circuses or companion animals. This results in greater consideration of the mental well-being of animals, an area which is now receiving more attention. For example, a new framework has been developed called the Five Domains which emphasises the need to consider the mental as well as physical well-being of animals.
The most common way to assess the emotional state of an animal is by observing and analysing behaviour, although there is increasing work being done on new technologies that assess brain function. In terms of behaviour, we can gain a greater understanding of an animal’s emotional state by looking for signs which reflect positive or negative experiences. For example, animals experiencing a positive mental state are likely to play, explore and have close social contact with other animals. Conversely, when an animal is frightened, they will either attack (fight response), escape (flight response) or may show no reaction (known as a freeze response).
Another way to assess emotional state is to let the animal choose different options in their environment. Given that animals seek pleasure and avoid pain, specific tests have been developed which allow the animal to show what they want and how important it is to them.
By observing animals for signs of negative and positive emotions, we can help ensure that their mental well-being is safeguarded so that they can experience a ‘life worth living’.
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