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Discussion Starter · #1 ·
I've been rearing d. auratus Panamanian Green & Blacks now (accidentally, as per previous posts!), and have had to euthanize a couple of tadpoles due to malformations - one where only partial legs developed (1 malformed front and 1 malformed rear), obvious SLS (only 1 out of 30, though!), and other deformations; and as per discussion board anesthetized with 5-6% ethanol solution for 15-30 minutes, then to a 70% ethanol solution for euthanasia. Recently have one that is tiny relative to it's egg mates, doesn't look symmetrical at all, and spins in wildly crazy gyrations that just don't look normal. Recently went to swap froglets for some plants locally, and that person indicates the ethanol method as described is horrifying because the alcohol burns it, so the most humane way is to put tad in water in fridge for 24 hours to put it into state of torpor, and then 48 hours in freezer. If I recall, I think the ethanol solution method was from Ed? (Who I read his comments religiously) and thought was the now preferred humane method, but now I'm second guessing. Again.

This community is filled with smart people. Any thoughts on which method I should use? The poor tad is not, methinks, destined for long and want to find the most humane way to move it along the karmic road.

Thanks one and all!
 

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Current guidelines permit ethanol immersion for fish (relevantly similar) as follows:

"Ethanol has been suggested as an acceptable alternative method for fish euthanasia.The depressive effects of ethanol on the CNS are well described, and exposure of zebrafish via immersion has become a model for behavioral and molecular responses to alcohol, at concentrations from 10 to 30 mL of 95% ethanol/L. At this dose, alcohol induces anesthesia, and prolonged immersion produces death via respiratory depression causing anoxia."

Cooling/freezing at any rate of temperature change is absolutely not considered humane as a primary method for anything other than neonate rodents, since ectotherms are not known to become unconscious at any temperature above freezing:

"Slow chilling or freezing of unanesthetized animals, including placing fish into a freezer without prior anesthesia, is also an unacceptable method."

The person you spoke to is incorrect, and it would be best to forward this information to them.
 

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We used to put fish in a paper towel then hit them with a 20 pound mallet to crush smaller fish. Could this method be used on tadpoles?/frogs? I thankfully haven't had to euthanize any frogs yet, but as I do plan on breeding more frogs in the future I would like to know. We thought instant and total destruction of the organism would be more humane then a chemical bath.

Also while not exactly related, in the entomology circles I've been apart of... it was and is often thought that putting invertebrates in the freezer puts them in a state of torpor, on the invertebrates and so is preferred when convenient over chemicals. I'm skeptical of this as ethyl acetate in a kill jar seems to work fast enough. I do freeze crustaceans but that is mostly so the physiology and color (as well as it can be) is preserved. I've not been able to find information on if this is true or not.
 

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We used to put fish in a paper towel then hit them with a 20 pound mallet to crush smaller fish.
I consider that a version of 'blunt force trauma' and so permitted, so long as the brain gets completely and instantly destroyed at the same time or before the body. I've culled tads and other small herps that way.

It has been credibly posted here by that insects are typically allowed to be killed via freezing by university IRBs. The linked guidelines, IIRC, dance around the issue of insects and similar inverts since essentially nothing is known about how they feel pain.
 

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Discussion Starter · #6 ·
Current guidelines permit ethanol immersion for fish (relevantly similar) as follows:

"Ethanol has been suggested as an acceptable alternative method for fish euthanasia.The depressive effects of ethanol on the CNS are well described, and exposure of zebrafish via immersion has become a model for behavioral and molecular responses to alcohol, at concentrations from 10 to 30 mL of 95% ethanol/L. At this dose, alcohol induces anesthesia, and prolonged immersion produces death via respiratory depression causing anoxia."

Cooling/freezing at any rate of temperature change is absolutely not considered humane as a primary method for anything other than neonate rodents, since ectotherms are not known to become unconscious at any temperature above freezing:

"Slow chilling or freezing of unanesthetized animals, including placing fish into a freezer without prior anesthesia, is also an unacceptable method."

The person you spoke to is incorrect, and it would be best to forward this information to them.
First. THANK YOU! I will definitely update this person with this info. Very appreciative of your time responding.
 
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