Sentience (pg. 79 and 104 of Nuffield Council of Bioethics)
Beings with less-developed rational capacities may be suffering more since they are not in the
position to conceptualise pain or suffering as means to an end. Humans, on the other hand, may
be better able to cope with pain, especially when they understand the underlying reasons or
purposes.
In addition, the nature of and capacity for suffering depends on the species. In humans and
some species, the loss of infants is emotionally devastating and debilitating, feelings that may
persist for many years and even throughout life. Animals such as rodents, which mate more
frequently and produce larger litters, do not display similar behaviours. Even if the whole litter is
removed, they return within hours and mate again.
Higher cognitive capacities (pg. 81)
Although it remain contentious that animals have different level of cognitive abilities, it is clear
that many animals are capable of feeling pain including animals which do not have exhibit higher
cognitive abilites (e.g. rodents) (see also box 3.2, pg. 81)
Capacity to flourish (pg. 82)
This concept extends that the focus is not just on avoiding pain and suffering that animals might
suffer, but also to consider what environmental enrichments can be provided to attend to
species-specific needs.
For example, some animals such as dogs, which are roaming species will not flourish if they are
kept in very small and confined pens for prolonged periods of time. But keeping animals in
unnatural environments need not always lead to welfare infringements. Animals that are bred in
captivity and are provided with sufficiently complex environment, may in principle be able to
develop to their potential in similar ways to animals living in the wild.
Sociability (pg. 84)
The species-specific needs that animals develop also include complex social interactions with
other animals. Animals have relationships among themselves and even with other animals (e.g.
primates, dogs). The expression of this behaviour is severely restricted in research and such
infringement cannot be alleviated in the same way as pain and suffering, the effects of which can
be mitigated by pain relieving medicines. Some argued that social animals should be housed in
groups or pairs. However, others argued that the cage size in conventional laboratories will
always be inadequate. The sociability of these animals should be taken into consideration so that
it doesn't cause distress or interferes with fluorishing to a significant degree.
Possession of life (pg. 85)
Some argued that humans and animals of similar cognitive abilities generates a right to life.
However, this view does not command wide agreement. Proper moral treatment of a being
depends on the characteristics it possesses, rather than simply on the species to which it
belongs. It can be argued that animals that possess one, or several, of these features of
sentience, higher cognitive capacities, capacity for flourishing and sociability, are moral subjects
and any treatment infringing on one of the features requires careful justification.