Do fish feel pain?

[OscarBaby]

Whether or not fish feel pain is the subject of debate in the scientific community. Since the answer to this debate is of great importance to us as fish keepers, especially those of us that treat our fish as "wet pets", I decided to share what I know about the academic debate. I have tried to synthesize and paraphrase the arguments below. A great source of information on this issue can be found here:

http://animalstudiesrepository.org/animsent/vol1/iss3/1/

Note that the above link is to a peer-reviewed academic article and the links below it are not references, they are responses/commentaries from other scientists that are not peer-reviewed. This is just a convenient source of information. There are peer-reviewed published articles on both sides of this argument.

++++++++++++++++++++++++++++++++++++++++++

On the “fish do not feel pain” side, the argument goes like this:

1) Pain in humans is associated with the neocortex, fish do not possess a neocortex, therefore fish are incapable of pain
2) Humans are too quick to assume a fish experiences injuries etc. the way a human would.
3) Aversion to a stimulus does not necessarily mean the fish is in pain.

On the “fish do feel pain” side, the argument goes like this:

1) Fish cannot tell us whether or not they are in pain, so we can’t tell if they are or not.
2) The structures of the brain associated with pain may be different in fish and humans.

Lately the debate has shifted to “What should the null hypothesis be”? In other words, what should we assume about fish and pain in the absence of any information on whether fish experience pain the same way we do?

1) Fish do not feel pain.
2) Fish feel pain.

The null hypothesis (Ho) is generally taken to be that there is no difference or relationship between two things. The null hypothesis might also written as the two things being compared are the same, since there is no difference between them. The alternate hypothesis (Ha) is that two things ARE different from one another or that there IS a relationship between two things.

So, which of these sets of hypotheses is correct?

Option 1 (the "fish don't feel pain" camp):

Ho: Fish are incapable of experiencing pain
Ha: Fish are capable of experiencing pain

Option 2 (the "fish do feel pain" camp):

Ho: Fish are capable of experiencing pain
Ha: Fish are incapable of experiencing pain

In other words, in the absence of new information, what is the safer assumption. Fish feel pain or fish do not feel pain?

++++++++++++++++++
Further background reading on this issue can be found here:
https://en.wikipedia.org/wiki/Pain_in_fish

As far as the neocortex arguments go, birds lack one as well but it has been Proven that they do feel pain.

 

[J. H.]

As far as the neocortex arguments go, birds lack one as well but it has been Proven that they do feel pain.

How?

 

[OscarBaby]

How?

Im having trouble uploading the screenshot of it, but the United Poultry Concerns article on Pain and Suffering in Birds written by Karen Davis, Ph.D on 14 July 2009 states that they do experience pain through pain receptors, thermo-receptors, and physical impact receptors responsive to noxious (tissue damaging) stimuli. These have been "identified in birds and characterized in chickens", and like mammals, who have a neocortex, when subjected to painful stimuli, chickens showed an increase in heartbeat and blood pressure, and "behavioral changes consistent with those found in mammals indicating pain perception." Including efforts to escape, distress cries, guarding wounded body parts, "and the passive immobility that develops in birds and other animals subjected to traumatic events that are aversive and that continue regardless of attempts by the victim to reduce or eliminate them (Gentle 1992)."

That's the first part to it, heres the link to it:
https://www.upc-online.org/thinking/pain_and_suffering.html

 

[Grinch]

I don't know what kind of evidence this is. All it proves is that fish don't feel pain in the same way we do. Noone can describe pain properly, if you want this kind of stufff to look like science, you need a psychologist.

Good points. "Pain" can be experienced in response to both physical and emotional stimuli in humans... can't the same be true of non-humans?

As far as the neocortex arguments go, birds lack one as well but it has been Proven that they do feel pain.

"Proven", or the p-word, does not exist in science. There is evidence for and against this issue (whether fish feel "pain").

Im having trouble uploading the screenshot of it, but the United Poultry Concerns article on Pain and Suffering in Birds written by Karen Davis, Ph.D on 14 July 2009 states that they do experience pain through pain receptors, thermo-receptors, and physical impact receptors responsive to noxious (tissue damaging) stimuli. These have been "identified in birds and characterized in chickens", and like mammals, who have a neocortex, when subjected to painful stimuli, chickens showed an increase in heartbeat and blood pressure, and "behavioral changes consistent with those found in mammals indicating pain perception." Including efforts to escape, distress cries, guarding wounded body parts, "and the passive immobility that develops in birds and other animals subjected to traumatic events that are aversive and that continue regardless of attempts by the victim to reduce or eliminate them (Gentle 1992)."

That's the first part to it, heres the link to it:
https://www.upc-online.org/thinking/pain_and_suffering.html

This is an interesting article, and is applicable to the larger question of whether or not mammals experience pain in the same way as other species. I would like to point out that the article you cite is not peer-reviewed, for what that is worth. All of the issues you cite (escape, distress cries, guarding of wounds) can be explained as adaptive responses as a result of a long history of natural selection (i.e. autonomic as opposed to a learned response).

 

[OscarBaby]

Good points. "Pain" can be experienced in response to both physical and emotional stimuli in humans... can't the same be true of non-humans?



"Proven", or the p-word, does not exist in science. There is evidence for and against this issue (whether fish feel "pain").



This is an interesting article, and is applicable to the larger question of whether or not mammals experience pain in the same way as other species. I would like to point out that the article you cite is not peer-reviewed, for what that is worth. All of the issues you cite (escape, distress cries, guarding of wounds) can be explained as adaptive responses as a result of a long history of natural selection (i.e. autonomic as opposed to a learned response).

Such is true, and for what its worth I have a chicken farm with around 3000 birds on site, and chickens, along with other species of birds, have a pecking order. Now, I'm not a scientist, but when a bird has its feathers ripped out of its bum by 10 other hens, I'm quite sure that scream is from pain and not "learned behavior"

 

[Grinch]

Such is true, and for what its worth I have a chicken farm with around 3000 birds on site, and chickens, along with other species of birds, have a pecking order. Now, I'm not a scientist, but when a bird has its feathers ripped out of its bum by 10 other hens, I'm quite sure that scream is from pain and not "learned behavior"

But, is the "scream" of the chicken "the best possible response" to the situation, in which case it might be evolutionarily conserved, or is it a visceral response to the present situation?

 

[OscarBaby]

But, is the "scream" of the chicken "the best possible response" to the situation, in which case it might be evolutionarily conserved, or is it a visceral response to the present situation?

When they scream it shows weakness so they get picked on more, but they can't help but scream. So I'd have to say a visceral response to the current situation

 

[Grinch]

When they scream it shows weakness so they get picked on more, but they can't help but scream. So I'd have to say a visceral response to the current situation

We are getting a little off topic here.

In birds, is it a visceral response, a learned response, or an anthropomorphism? Basically the same question with respect to fish. Following the argument of Key, birds do not have a neocortex, therefore they do not feel pain.

 

[Fizzicks]

Well, it's pretty simple. We're at the point where we don't know if they do or don't. So we should probably assume they do. And try to be as humane as possible till science tells us other wise.

Then if they don't. We can just assume their fleshy robots and do what ever madness we desire.

 

[skjl47]

We can just assume their fleshy robots and do what ever madness we desire.

Hello; back when I used live bait, read minnows, I was told they did not feel pain by older fishermen. I was instructed as how to insert a hook into the minnows in various ways. Thru the back, in the mouth and out near the eye, thru both lips and so on. It was convenient for me to believe that at the time.
It may be that having such a possible "myth" allows for the treatment of fish in these ways so we do not feel guilty.
I have heard the same sort of thing said about live lobsters going into a pot of boiling water.

As I grew older I came to the notion that fish and other animals experience something that may as well be called pain. Maybe not just like people experience pain, but a decent enough imitation that they have fooled me.

When a child of six to the age of ten I had to catch and kill hens to go on the supper table. It was a part of daily life the same as the slaughter of hogs or other food animals. I did it quick and enjoyed the chicken my mother cooked. I still eat chicken, pork, beef, fish and such. Even tho I now think these animals can feel pain and I no longer have to kill them myself, I know someone does the deed. Has not stopped me from eating them. Had a ham sandwich for lunch and salmon for supper.