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Scientists Revive an Absurd Question: Do Animals Feel Pain?

A zoologist is among those now debating whether fish feel pain; believe it or not, veterinarians once debated the same thing about cats and dogs.

Dr. Eric Barchas  |  Mar 31st 2015


I love most aspects of fishing. I love being on or around water. I love hanging out with buddies, drinking beer outdoors, and talking about nothing. I love traveling to the sorts of exotic places where really amazing fishing can occur.

For me, however, fishing has one fatal flaw, which has made me swear off the hobby. I am referring to actually catching a fish. I cannot stand the sight of a fish writhing on a fishing line or flopping helplessly on the ground or the deck of a boat. When I most recently was in the Peruvian Amazon, several members of my group spent much of their time spearfishing. It was then that I learned that I also cannot stand the sight of a fish writhing in agony after having been speared.

Call me a softie, but I can’t tolerate the sight of an animal in pain. To me it is self-evident that all advanced animals, and at least all vertebrates — a category that includes fish — feel pain in a manner similar to how people feel pain. I also have no doubt that some invertebrates, such as the octopus, similarly experience pain.


Photo of Dr. Eric Barchas by Liz Acosta

Therefore, I reacted with disbelief to an article in the Jan. 1, 2015, issue of the Journal of the American Veterinary Medical Association, titled “Debate continues over whether fish feel pain.” Here is a quote from the article:

Do fish feel pain? Can they suffer?
Historically, the opinion on both counts has been that they don’t,
but these views are rapidly evolving as scientific evidence expands.

Unsurprisingly, those who believe fish are not capable of experiencing pain or suffering are led by a crusty old codger (or, as he is known in academic circles, a professor emeritus). Again, from the article:

That fish respond to injurious stimuli unconsciously and aren’t
actually aware of pain is a view championed most notably
by James Rose, Ph.D, professor emeritus of zoology at the University of Wyoming.

Enough about fish. Rose and I will never agree on the matter. History will prove that I am right and he is wrong.

Cat with fish tank by Shutterstock.’>

Cat with fish tank by Shutterstock.

As I read the article, I was reminded of a similar debate about pain that occurred many years ago. The question then was whether cats and dogs felt pain.

I’m not kidding. There was once a debate about whether cats and dogs are capable of suffering and feeling pain.

In fact, for most of the history of veterinary medicine, the opinion about cats was similar to the feelings expressed by Dr. Rose about fish: denial. Never mind that cats are mammals with fully developed nervous systems extremely similar to those of humans. Never mind that cats clearly exhibit signs of distress and pain, ranging from posturing to vocalizing to pained facial expressions.

Nope. For most of history cats were thought to respond to injurious stimuli unconsciously. Until, that is, a vanguard of scientists and veterinarians in the 20th century began to push back. They used weapons such as studies that showed, shockingly, that cats showed less of a response to an injurious stimulus (such as surgery) when painkillers were administered. They mapped out the feline nervous system, with nociceptive (pain) receptors and pain centers in the brain that were strikingly similar to ours.

Gradually, resistance to the idea that cats feel pain began to fade away. I suspect this happened as the crusty old codgers who didn’t believe in feline pain died off and were replaced by more forward-thinking people.

Sleepy cat by Shutterstock’>

Sleepy cat by Shutterstock

That should have been the end of the debate, but it was not. Once a belief in the existence of feline pain became more or less universal, there arose a powerful contingent of veterinarians and scientists who argued that cats should not receive painkillers because pain was good for them.

Their now completely debunked argument went like this: If a cat had a broken leg, it was best not to administer analgesics because pain would keep the cat from using the leg and the leg subsequently would heal faster. Similarly, pain from surgery would keep a cat from being too active too soon, or from licking the incision.

Incredibly, opponents to pain control in cats were not unheard of when I was in veterinary school in the 1990s. But by then they were few in number and desperate, and their arguments showed it. Some of them acknowledged that cats could feel pain and that pain was bad; however, they argued that the side effects of most painkillers in cats were worse than pain.

The argument over whether cats feel pain, and whether pain is bad, and whether painkillers are better than pain has been dead for over a decade. I imagine that the death of the debate coincided with the deaths of the final remaining members of the pain-is-good contingent.

The universal effect of the infamous Sarah McLachlan spots on cable TV show that belief in and horror at mammalian suffering is ubiquitous among the general public. I am happy to say that it is similarly ubiquitous among veterinarians. Now the only debate about feline pain centers around how best to prevent and treat it.

In time, the same will be true for fish.

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