Sciencemadness Discussion Board - Fish euthanasia

Fish euthanasia

Nixie - 28-12-2006 at 18:28

A goldfish went up the gravel vac tube and by the time I managed to shut it off, both eyeballs got sucked out of their sockets. The fish is appears otherwise undamaged, but I fear it will starve as it's too slow finding food by the time the others eat it up (nostrils are of limited use because of strong current from the filter).

I'm considering euthanizing it. The two most common methods I've come across are a) anesthetize with clove oil then add alcohol, but I don't have clove oil, and b) benzocaine HCl, which I also don't have. I do, however, have benzydamine HCl and I'm wondering if that'll also work painlessly.

By the way, jokes about feeding the goldfish to my cat are not welcome. It may happen in the wild, but the salient difference is that this is my fish rather than a fish, and I've come to care about it.

[Edited on 29-12-2006 by Nixie]

Maya - 28-12-2006 at 20:04

Sad, so sad......... my condolences.

My sharktail commited fish harikari yesterday by jumping out of the tank onto the floor

my advice is to give him a proper toilet funeral as all fish deserve

Ozone - 28-12-2006 at 20:18

My condolences,

We used to use an anaesthetic called Finquell to euthanize fish in the lab, but this stuff, also known as M-222 might be hard to get. Following that, there seems to be something to the clove oil bit--but, an emulsifier is required. Here is a link to a forum where milk (do not use EtOH, it causes the fish pain) was used as the emulsifier:

http://p103.ezboard.com/fthegoldfishandaquariumboardfrm13.sh...

Best wishes,

O3

Nixie - 28-12-2006 at 21:45

Maya, I hope you didn't mean flushing the fish down the toilet while it's still alive. That just makes it fast and easy for me, not the fish with chlorine burning its gills.

I've decided to see over the next few days if it will manage to eat food and stay clear of infection. Who knows, it might make it so I'll give it a chance. But I tell you, it looks nasty because black moors have enormous eyeballs and the empty sockets are most of the size of the head... now you can see light diffusing from the opposite eye socket through the thin separating tissue in the middle...
I already have another damaged fish, an oranda that scratched its eye which was subsequently sucked out by a dojo loach...

There are small strings of tissue streaming from the eye sockets. Should I cut them off or let them rot off/other fish eat them?

Twospoons - 28-12-2006 at 22:10

Would freezing work? Its supposed to be a humane way to kill crayfish / lobsters - as opposed to dumping in boiling water.

Nixie - 28-12-2006 at 22:21

I guess dropping into ice water would be nearly instant, as goldfish are pretty sensitive to thermal shock.

Lobster is quickly killed by driving a wide blade knife straght down into the cross indentation on the back top of the head. It's a distributed nervous system so the need for a large blade to make a long cut. If you put them in the fridge for 20 minutes they become very lethargic and then it's easy to do that procedure. I never had the heart to put a lobster alive in boiling water...

But that's food, whereas I don't want to deal with goldfish blood and guts... I'm grossed out enough cutting the bloody steaks from the store.

I'm still wondering about whether benzydamine HCl will work as well as benzocaine HCl. Both are analgesics and are chemically related substances.

Maya - 29-12-2006 at 04:22

Yes Nixie, definitely put him on a block of ice or else in the freezer , that way he will feel no pain. 'Tis no way for a fish to live unfortunately. I would fix the fishtank ASAP.
If you have a yard or garden then make use of it if not too cold otherwise it'll be alright to flush him after he is frozen

Again my deepest condolences on your loss

Blind Angel - 29-12-2006 at 07:24

I'm supporting the freezing water way, that's the way my brother was using with his fishes (vs. my idea of using cyanide). It's way more simple and will give you the same effect (non-painfull death)

garryb - 29-12-2006 at 07:30

I'm no expert, but in the UK it is quite common for goldfish ponds to freeze in winter, yet goldfish survive until spring provided they have not frozen completely solid - of course the water under the ice layer is not quite 0 degrees Celcius, but it is presumably not far off in a cold winter, so I'm not sure that cold water as such will kill the goldfish - or is it the intention to chill the fish then kill it by other means? Or perhaps a sudden immersion in icy water (as opposed to the gentle drop of a natural winter) is lethal?

Nerro - 29-12-2006 at 08:57

Putting wodka in the freezer and putting the fish into icecold ethanol solution might be another idea. The ethanol will subdue it and the cold will finish the job...

YT2095 - 29-12-2006 at 09:36

Shotgun!

it won`t feel a thing, I promise you

Maya - 29-12-2006 at 09:42

You can't really mean that can you???

That is so cruel

, This poor creature has undergone a terrible experience and now you wish to subject it to torture? Unbelievable!! :mad:

Niels Bohr - 29-12-2006 at 10:18

Try FETM

12AX7 - 29-12-2006 at 17:20

How do you figure? Seems to me exactly like the guillotine: a rather gruesome method, but assuredly instantaneous and without sensation (if it works properly, as some monarchs have been unfortunate enough to experience otherwise).

Along similar lines of morbidity, anything that causes instant disfigurement to the nervous system is going to do it. Smash the head with a hammer, etc.

In terms of chemicals, how do fish respond to ether or chloroform? Chloral?

Tim

UnintentionalChaos - 29-12-2006 at 20:46

Do you put a tiny rag with chloroform over the fish's gills while it's swimming around?

I doubt you have any cyanide salts around, but a spoonful of those in a small fishbowl would probably give the quickest, least painful death possible. For a human a small pill would take a few minutes. To a fish, the cyanide would pass directly into the blood through the gills (think HCN to humans) and would be much faster acting due to the small size of the fish. I'm no biologist/biochemist but that seems like a plausible effect to me.

[Edited on 12-30-06 by UnintentionalChaos]

Nixie - 29-12-2006 at 22:02

Haven't put it down yet. It seems to have recovered from the shock and is swimming around with surprising obstacle avoidance. Unfortunately, it doesn't seem to be able to find the food at all. Maybe it's the dry food doesn't have much scent, or maybe the olfactory system has been destroyed by the suction, and I don't know if it can recover and thus whether it would be worth it to feed it manually.

[Edited on 30-12-2006 by Nixie]

Waffles - 29-12-2006 at 22:07

Quote:

Originally posted by Nixie
both eyeballs got sucked out of their sockets.

That is the stuff of horror movies. Yeeeesh.

Cheapest for you + easiest + least painful is probably putting the alcohol (ethanol or vodka) in the freezer for a day, and putting the poor thing in.

The quickest and most certain is probably the cyanide method- that is the way I would personally do it if I were in as horrible a situation as you are. On the other hand, that's because I have lots of cyanide salts sitting around.

Or you could just wait for the creature to become an aquatic Hellen Keller?

Maja - 31-12-2006 at 03:15

You all are a little crazy .... Just dump down the toilet .... Or you really care about their feelings and kinda shit ? Maybe you are vegetarian ?

Nixie - 31-12-2006 at 04:22

It's simple -- it's a pet. If you had a sick dog, would you throw it in the sewers alive?

12AX7 - 31-12-2006 at 08:55

Arguably, a dog is a more advanced animal than a fish. . .

bereal511 - 31-12-2006 at 11:01

Eh, I think it's a bit off topic to give opinions on what is and what is not important to a person in terms of pets. Sure, a dog is more advanced than a fish, but if I've had that fish for 5 or 10 years, I'm going to want that fish to live or at least die comfortably.

I'd go for the freezing if you decide to have a fish euthanasia. It seems like the Carp family doesn't survive well in those temperatures, so it should just simply go into a slower metabolism until it finally drifts off into a painless death.

h0lx - 31-12-2006 at 11:03

You say you want a non-painful death? You should have just killed it with a hammer or any other quick and simple way after the accident. Talking about torture you are torturing him already with big wounds in the face. The faster you execute it the less it will be tortured. I imagine I'd want to be killed right away after my eyes are sucked out, as the eyes are one of the most painful parts of the body.

Blind Angel - 31-12-2006 at 14:17

Yup, but the nerves are already broken so no more sensation on that side. Final note: go for the cold.

evil_lurker - 31-12-2006 at 15:24

Bah.

Blenderize it.

Death in .02 seconds., nerves won't have time to react.

enhzflep - 31-12-2006 at 15:55

Huh? There's a pair of points you've clearly missed evil.

Firstly, nerve impulses travel in the human body at roughly 400kmh, which is 111.1 m/s. Assuming a comparable rate in fish, this would be equivalent to 2.22 meters in 0.02 seconds.

Secondly, which part/s of "It's simple -- it's a pet." or "this is my fish rather than a fish, and I've come to care about it." was too hard for you to understand?
This isn't 10 years ago, and it's certainly not Iraq. Putting live animals through machines designed to chop and pulverise doesn't exactly fit the definition of euthansia.

Sorry to hear about your impendinding loss Nixie. We had the heater thermostat croak it one night. The next morning the house smelled like a fishmarket on the 3rd day.. Poor little guys. Lost about 8 loaches, an Angelfish and a Catfish that night. They weren't even my pets and I felt terrible for them. I don't envy the position you find yourself in now a single bit. At least in my case they were already departed by the time I found them.

[Edited on 1-1-2007 by enhzflep]

Nixie - 31-12-2006 at 19:45

Actually, it's now actively seeking out food, and it took a shit so it's managing to find some of it at least. I've decided to let it live unless I see it losing a lot of weight or any behavioral symptoms of a problem (all the distress it was in initially seems to have passed now).

Unortunately, another fish has a problem now... I've had a small one-eyed oranda (scratched its eye, then a dojo loach sucked it out for a snack), and now suddenly its mild flip-over has gone full blown and it's floating at the surface upside down... I read you can implant an aluminum weight in the belly to upright them but I don't know how to do that properly, or that any vet in Vancouver would handle fish. I tried feeding frozen pea pieces as they are supposed to unblock the pneumatic duct but it spit them out. Or it could be that the antibacterial I put in the water after the accident from the first post disrupted its gastric fauna causing gas buildup. I'm unable to tell if it's a GI tract or swim bladder issue, so I can't see how to treat it.

Sigh, I don't think I'm very good at taking care of fish... and these ornamental goldfish seem to be somewhat handicapped by their unusual shapes and inbreeding. I almost always get ick unless there's a bit of salt in the aquarium, for example, despite having good water quality as a result of a lot of flora in the tank.

[Edited on 1-1-2007 by Nixie]

lost another

Maya - 1-1-2007 at 12:19

Glad to hear your fish is showing signs of recovery Nixie.

My poor little bottom feeder just up and died this morning

Now I'm back to 3 tetra's and a sharktail

I think this new sharktail that I got to replace my old one that died killed my bottom feeder by being too aggressive and bullying him to death :mad:

Ramiel - 2-1-2007 at 04:12

Does anyone else look at this thread with a bit of confusion? Perhaps it's just being brought up around farms, with two parents who learnt life on a farm, you see death all the time...
I honestly don't mean to sound like an asshole, and I suspect that I've lost something in terms of sensitivity, but could you just take the fish outside for a brief introduction with a spade, or the heel of your gumboots? seriously, just take a good chop at it with the blade of a spade, la guillotine est une manière parfaitement humanitaire pour qu'un poisson meure.

Never mind that fish of that size probably don't feel pain and any agitation is more like a robotic mechanism than any anthopomorphic distress.

Nevermore - 2-1-2007 at 05:09

an easy way would be to sewer the central nervous system from the rest of the body, cut the head off with a sharp knife and the result trauma at the nervous centres would do the job.
if you want to be even more sure, cut THRU the brain, the fish skull is soft and easy to cut. no brain no pain..
i do not have enough knowledge of the physiology of fish to tell what chemical would work, you could surely overdose with tranquilizers, but..do they work for fish?
i'd go for the knife, i saw how they do sushi in the traditional way, they stuck a big sharp nail in the back of the head then cut the fillets.
the fish dies immediately by neurologic trauma.

Nixie - 2-1-2007 at 05:25

Ramiel, I've been on a farm and even chopped off a chicken's head with an axe (I was about ten at the time). A bit hard to do accurately with a neckless animal such as a fish. But the main thing is, and I'm repeating this, that this fish is my pet. People die all the time but we don't pay attention. But if your friend dies, I bet you'd be quite upset.

As for pain perception, the fish have the sensory apparatus, and inflicting pain on them alters their behavior as is well known. Additionally, analgesics are effective in fish, observed when such changed behaviors were normalized when analgesics were administered:

Sneddon, L.U. (2003) The evidence for pain in fish: the use of morphine as an analgesic. Appl. Anim. Behav Sci. 83, 153-162.

Wagner, G.N., Singer, T. D. and McKinley, R.S. (2003) The ability of clove oil and MS-222 to minimize handling stress in rainbow trout (Oncorhynchus mykiss Walbaum). Aquacult. Res. 34, 1139-1146.

Obviously the subjective experience cannot be correlated to that of say a mammal as the brain is quite different, but that doesn't mean there isn't one. Just because a fish doesn't feel pain the way you do doesn't mean it doesn't feel it at all.

[Edited to add references]

[Edited on 2-1-2007 by Nixie]

Veruth - 2-1-2007 at 10:31

Honestly, my solution would be some sort of massive physical trauma, but I get the idea.
Even if a solution is no longer needed, it's still an interesting problem.
What about KCl, I know it works well in mammals, but I have no idea about fish.

Maya - 2-1-2007 at 10:59

He was a decent fish,

He was an honest and decent fish,

He gave his life selflessly in pleasing his master,

He was a decent fish

Nixie - 2-1-2007 at 17:32

There's no KCl here, except in Half-Salt which is a half sodium and half potassium chlorides substitute for table salt (I recommend it, more people could use a reduction in sodium and more potassium, and there's no difference in saltiness).

Anyway, the oranda I mentioned above that was floating worsened a lot suddenly and was barely responding to prods. The only thing I had on hand was benzydamine HCl for oral use. I just added it slowly to a container of tank water I had the fish in. At one point the fish felt something wrong and got slightly agitated, but that lasted about 3 seconds and it was motionless.

I dissected it afterwards and looked like the intestines were clogged and had pockets of air as well. These ornamental goldfish bred for their distorted shapes have their guts squeezed together in ways that probably make this a more common problem than with regular fish...

The downside with chemical killing is I couldn't feed the body to the cat. On the other hand, might be as well since a sick fish could have parasites or something.

[Edited on 3-1-2007 by Nixie]

Poor goldfish

grn - 29-1-2007 at 15:27

Many fish find food by the use of their lateral line and other keen senses. I have a pleco without any eyes. The goldfish might spend his time sucking the bacteria from the rocks on the bottom of the aquaria as a food source. Euthanasia could be done with ice and salt.

Quote:

Originally posted by Nixie
A goldfish went up the gravel vac tube and by the time I managed to shut it off, both eyeballs got sucked out of their sockets. The fish is appears otherwise undamaged, but I fear it will starve as it's too slow finding food by the time the others eat it up (nostrils are of limited use because of strong current from the filter).

I'm considering euthanizing it. The two most common methods I've come across are a) anesthetize with clove oil then add alcohol, but I don't have clove oil, and b) benzocaine HCl, which I also don't have. I do, however, have benzydamine HCl and I'm wondering if that'll also work painlessly.

By the way, jokes about feeding the goldfish to my cat are not welcome. It may happen in the wild, but the salient difference is that this is my fish rather than a fish, and I've come to care about it.

[Edited on 29-12-2006 by Nixie]

Nixie - 29-1-2007 at 17:55

Huh? I never imagined nitrifying bacteria can be food for goldfish.

Anyway, the fish seems to have adapted fine and appears otherwise healthy. Though I wouldn't be surprised if it takes it a while to figure out how go eat when I switch back to floating food.

[Edited on 30-1-2007 by Nixie]