Science, values, and animal
welfare
D. Fraser
Agriculture and Agri-Food
Canada, Ottawa, Canada
Confusion often arises
because the role of values in scientific approaches to animal welfare has
been inadequately articulated. Different workers tacitly disagree over
whether animal welfare should be treated as (1) a single, measurable attribute,
(2) a single attribute that cannot be measured directly but can be estimated
by combining contributing attributes, or (3) a concept involving multiple
attributes whose relative importance cannot be established in an entirely
objective way. Workers in the first category propose single, objective
measures of welfare, such as longevity and levels of stress-related hormones;
however, this approach rests fundamentally on judgements, which are not
purely objective, about the relative importance of different factors for
an animal's quality of life. Studies of animal preferences and motivation
are sometimes seen as an objective way to weight different attributes according
to the animals' own priorities, but there are numerous technical and fundamental
limitations to this approach. Animal welfare is best conceived as a concept
incorporating multiple attributes, with considerable consensus over certain
general principles but disagreement over how the principles should be applied.
Because the various attributes cannot be combined in a purely objective
way, science is limited in its ability to determine the "overall" welfare
of an animal and to compare welfare in disparate environments. Instead
of attempting to "measure" animal welfare, the role of science should be
seen as identifying, rectifying, and preventing animal welfare problems.