Feeding and Nutrition :: feeders

[kmichael55]

I read on here a while ago about someone humanely killing feeder fish with hot water to feed to turtles..can't find the post. I would like to try this but wanted other's opinions on it first. I have a 10 gallon tank of feeder fish and whenever I put some in the tank they become friends for the turtles until I remove them and put them back in the feeder tank during a water change. They're just too fast for my turtles. I have had these fish for so long and have nothing to do with them. I, of course, would only do this as a treat every once in a while.

[DavidY]

I've heard the same thing suggested by others before too. I have no idea how true it is, but it does make a little sense. I think the sudden shock would nullify any lingering if not all of the pain and death would quickly follow. It still seems harsh though. I've heard of others who have put the fish in a small container with water and then bubble pure CO2 through an air line tube into the water. The fish goes unconcious for like 5 minutes. This is usually done for research purposes but it would probably work just as well for euthanasia. Another method that field biologists use is electric shock, but I doubt you'd want to mess with that.

[kmichael55]

Is there any risk though with my turtles eating dead fish? I've heard not to feed any fish that have been frozen because of an enzyme that makes the turtles not be able to digest something. It seems OK, since the fish are healthy, just wanted to make sure.

[marisa]

Thiaminase is only present in some kinds of fish, not others.

[kmichael55]

Thank you, I had forgotten the name, I looked it up, and it seems that rosy red minnows and goldfish do contain it, and that the reason freezing is a problem is that it causes the cells containing thiaminase to rupture. It is the enzyme that destroys vitamin B1. So it seems that maybe rosy red minnows are not a good feeder fish. I had never heard of this before, but I buy guppies anyways. The site also says it shouldn't be a problem if fish are fed how they are supposed to, as a treat. It's only a problem for diets that are mostly fish.