Dr Michael Morris - Animal welfare writer Dr Michael Morris has a PhD in zoology from the University of Auckland. He is presently teaching degree courses in environmental management at the Bay of Plenty Polytechnic.

Science has a high standing in Western culture, and this can be seen in the way it is brandished as a blunt instrument in political discourse. If anyone wants a real argument clincher in debates on animal welfare or any other controversial issue, then an appeal to "sound science" as opposed to "emotion", is usually enough to convince politicians to give in. As the Ghost Busters so eloquently put it, "back off man, I'm a scientist".

Since science is looked upon so highly, it is worth examining just what constitutes the particular branch of mandated "animal welfare science" used with such effect by the agricultural industry and their allies among the academic community to justify the continual ritualistic abuse of animals in sow stalls, farrowing crates, battery cages, cattle trucks, slaughter houses, rodeos and other traditions of our culture.

The truth is that there are different types of science, comprising such fields as traditional knowledge, field work, inferences from observation, and arguments from analogy. But it suits the animal industrial establishment to concentrate on only one scientific paradigm; the use of repeatable laboratory measurements of physiological variables. The rich possibilities of scientific enquiry are captured by the animal industries, and constricted as tightly as a sow in a crate.

So industry influenced scientists measure the reproductive output of pigs in crates and infer that because they are just as fecund in captivity that they must be happy. They measure cortisol (stress hormone) in chicken pooh and conclude that hens in cages are not stressed.

The science of animal welfare is inherently complex given that it involves reducing something that is not readily amenable to scientific study (the personal feelings of an animal) into something that can be measured. Because of this difficulty, it was once considered somehow "unscientific" to make any inferences about animal feelings from an observation of their behaviour. However, there is nothing "unscientific" about making inferences by analogy; it is something we do all the time. The argument from analogy is in fact used to great effect by top scientists with no affiliation with the agribusiness industry. These scientists start with the premise that animals have the same sense organs, nervous systems and behavioural repertoire as humans. It is therefore reasonable to infer that they feel the same way as a human when killed, mutilated or confined in barren environments.

If the entire arsenal of scientific enquiry is used, it is not hard to find flaws in the narrow arguments of the animal industry. Stress hormone in hens is only one indicator of poor welfare; boredom is just as debilitating as stress. And as everyone knows, having lots of children does not equate to happiness. A sow in a crate may be just as fecund as one in the wild, but their aberrant behaviour tells everyone that they are far from happy.

The next time an industry representative tells you "back off I'm a scientist", it would be well to ask them what kind of science they are relying on.