Yesterday, I gave a lecture at the International Association for the Study of Pain in Milan Italy. My lecture was part of a non-human species special interest group which addressed ethical issues and other challenges regarding pain research in animals.
The need for providing pain relief for animals is important, whether during a surgery (e.g., castration and dehorning of cattle) or treating chronic osteoarthritis in cats, dogs and birds.
What scientists now appreciate is that every species is unique and requires different strategies for both assessing pain and studying ways to relieve pain. For example, cats may actually purr when injured or ill or in pain — not something that every owner or even every veterinarian recognizes. Because cows are prey animals, they often attempt to hide illness and pain and hence may show few signs.
Several scientists at the special interest group meeting discussed animal models and how research using rodents does not always translate to efficacy in humans. In some cases, pain research findings in rats does not translate to findings in mice. For example, burrowing behavior in rats can be measured as an indicator of pain. Rats will burrow more if pain-free. This finding, however, does not occur in research mice.
My lecture discussed the need for better medications to control or eliminate pain in animals. I also stressed that when such research is done — it should be done without harm to the animals and with a high probability of success for products and strategies that directly benefit animals (i.e., not just people).