In late August I participated in a 4-day conference in Montreal. The 8th World Congress on Animals and Alternatives in the Life Sciences drew over 800, mostly scientists. The mission of the meeting was to advance “the 3Rs,” which aim to Replace, Reduce, or Refine (i.e., lessen the suffering of) animals used in research, testing, and education.
I mingled with people representing a wide range of viewpoints, from groups like Americans for Medical Progress and the New Jersey Association for Biomedical Research, whose mission is to defend the continued use of animals, to organizations dedicated to ending harmful uses of animals as soon as possible, like the Physicians Committee for Responsible Medicine, InterNICHE, PETA, AnimaLearn, and EuroGroup for Animals. My own paper, which used records obtained through the US Freedom of Information Act to chronicle the miserable lives of primates in two American laboratories, was one of several from The Humane Society of the United States.
Some of the presentations were stark reminders of just how sensitive animals are to the intrusions of humans on their lives. For example, just being transported to a new location was so stressful to caged rats that their body weight, heart rate and blood pressure aren’t back to normal two weeks after being moved, and their levels of activity and blood corticosterone (a hormone associated with stress) never returned to pre-move levels. A Canadian wildlife veterinarian presented data showing that the health of polar bears declines each time they are subjected to the stress of being captured (for study). The more times caught, the worse their physical condition becomes. The presenter asked his audience to imagine how stressed we would feel to be chased and caught by predatory aliens. Wild animals may struggle so hard to escape human capture that they are vulnerable to “capture myopathy,” irreversible muscular damage that can cause permanent lameness, even death.
But the great bulk of animal research is the kind done in laboratories. One of the sessions I attended focused on animal pain, with an emphasis on rodents. Disturbingly, pain research on animals is a thriving enterprise, and the past decade has seen a dramatic increase in research that deliberately subjects mice to unrelieved pain. All mammals process pain along the same neural and biochemical pathways, so it strikes me as a prejudice that rodents are commonly thought of as “lower mammals” whose pain and suffering is somehow less worthy of our concern. New studies further expose this prejudice. We saw video clips of mice being marked by having small holes punctured into their ears with a hand-held hole-puncher. This common laboratory method is routinely done without anesthesia. The mice squinted their eyes, opened their mouths wide and struggled violently in response to the assault. Rabbits having their ears pierced with a tattoo hole-puncher reacted similarly. The presenter told us he had the audio turned off so that we wouldn’t have to hear their screams. A video of a rabbit whose ear had simply been treated 20 minutes earlier with a topical anesthetic showed no pain response, and the presenter implored researchers to use this simple refinement.
Contrary to earlier belief, rodents and rabbits—which like many animals have evolved stoicism to avoid detection by predators—do show detectable pain on their faces and bodies. So reliable are these subtle pain responses that a research team has developed a Mouse Grimace Scale (MGS) that quantifies the severity of pain based on orbital tightening (eye closing), nose and cheek bulging and ear and whisker positions. A similar Rat Grimace Scale has since been developed. Even a complete novice can learn to recognize a rodent’s pain with just ten minutes of training.
I asked if a mouse’s pain might endure after grimacing stops. Yes, it’s fairly certain that it does. For example, we stop grimacing long before the pain of a sprained ankle or broken bone is gone. And yet, while human patients typically request and receive pain medication for 1 – 2 weeks following surgery, animals in laboratories (including the primates whose lab records I examined) typically get 1 – 2 days, and sometimes no pain relief at all.
This is all the more sobering considering that tens of millions of rodents are currently used in experiments, and a single research lab may have over 100,000 mice. I and a growing number of my scientific colleagues share the view expressed recently by the noted British biologist Richard Dawkins that “we have no general reason to think that non-human animals feel pain less acutely than we do.”
Some may conclude that the challenge is to reduce the pain and suffering of animals in labs. But I think this information demands another conclusion: we shouldn’t be using them at all, for the same reasons we don’t use humans.
Defenders of vivisection declare that animal research is “a necessity.” This is like saying that capital punishment is a necessity. Whatever one thinks of it, we are not bound to do it. We do it by choice, so we can choose not to. To me the most compelling reason to desist is that animals feel pain and suffer essentially like us. That being the case, there really is only one morally defensible “R”: Replacement.
Image Source: Audery_sel (via Flickr)