What is the most humane way to euthanize a reptile?

[MicroZooKits]

This is sort of a dark topic I know, but there comes a time in a keepers/breeders life where they will eventually have to make this decision.
When an animal cannot care for itself or is suffering from a disease or has sustained a life threatening injury and is only getting worse, a lot of people believe that it's best to just let that animal rest in peace rather then go through life suffering. I had a baby Savannah monitor a couple years back that had the weirdest disease where it eventually needed help to eat, drink, and defecate. Pretty much turned into a lifeless vegetable. He had actually drowned in the sink during a soak one day (during a manual defecation session) and I brought him back with CPR but after that it seemed that he no longer had the desire to live. He had the weirdest blank look in his eyes, didn't bask, eat, or do anything on his own. We kept him alive for another week or two after that day then we decided it was best to just let him go. We made him a little coffin, lined it with plants and flowers, said goodbye as we put the lid on and into the freezer he went. Sad as it was it was the best thing we could've done for the poor guy. We weren't about to let him starve to death or continue to keep him alive against his will. Two years later I face the same predicament. I just hatched a baby leopard gecko that has a severe neurological disorder that prevents him from walking and balancing. He is about a week old now and has shown no sign of improvement. I have manually fed him the last couple days to try and encourage development, but I don't think it's going to happen. Today he was "lost" in the lid of a pickle jar totally disoriented and I felt really bad for him.
I don't want to manually feed him every day because he's too discombobulated to hunt on his own, and I don't want him to starve either.
It's coming down to that point of judgment again and I want to be sure that if I have to do the duty that it's done right and with as little discomfort as possible. I understand the quickest most painless way but I don't really want to deal with a horrifying memory of being the executioner. Things like that stick in my mind and arise at the wost times possible.

 

[DAND]

I have always used the freezer method but you could always go the dry ice/CO2 method.

 

[hhmoore]

While freezing was once considered a humane option, what I have seen more recently indicates that reptiles do not just "go to sleep" in the ice box. Things seem to point toward that method being quite painful, and a rather inhumane choice. I've never tried a CO2 chamber (many people use them for dispatching rodents, esp in quantity); but one member that did reported that it wasn't a good experience & he would never do it again. So much for the ways that would probably leave you with the clearest conscience.
Cervical dislocation is probably a reasonable option with smallish to medium sized specimens, but it would definitely leave one in the executioner role. Heart sticks, or various meds are also options...but not everybody has the access or skills.

(I still use the freezer for the occasional deformed hatchling)

 

[Mokele]

IMHO, the most human methods are halothane (gaseous anaesthetic) overdose or intra-cardiac injection of sodium pentabarbital. The latter is quicker and requires less specialized setup (though it's illegal for the individual to possess), but can be difficult for large animals. Both require a vet.

The freezer used to be[/b] acceptable, but more recent studies suggest that ice crystals form in the extremities before unconsciousness, leading to unacceptable levels of pain. Research labs are now no longer allowed to use it. (Although apparently it can work if you use liquid nitrogen - but that's not exactly something most people have access to).

CO2 is actually not a very good idea - the trigger for respiration is high blood CO2, not low oxygen, so the animal will 'freak out' as it feels itself unable to asphyxiate. Death would be due to blood acidification, not due to lack of oxygen, since herps require very little O2.

Cervical dislocation is similarly problematic. Because of their low metabolism, CD or decapitation would not cause instant death, and in species such as snakes, it could take minutes or hours.



Unfortunately, this rather leaves anyone who isn't a vet in a tight spot. The chemicals for truly humane methods are illegal to own privately, and the other methods are inhumane.

My recommendation is a slow cooldown, possibly in the fridge. This shouldn't cause the ice-crystal problem, but will put the animal to sleep. From there, you can try various things, such as the freezer, with less qualms. Honestly, I'd recommend double-pithing (inserting a sharp probe into the brain via the base of the neck, and quickly "scrambling" it, then doing the same for the anterior spinal cord) after deep refrigeration, but that requires even more skill than cervical dislocation, especially on small animals.


So, IMHO: Fridge first, then freezer. It may not be 100% like anaesthetic overdose, but the use of the fridge will make it the most palatable method.

Also, for anyone reading this who needs to euthanize amphibians - most specialty tropical fish stores (and many such websites) sell a compound called MS-222 or Tricaine. It's harmless to anything with an impermeable skin (reptiles, mammals, birds), but will anesthetize any amphibian simply by immersing them in a bath of it. For anesthesia, use 250 mg/L, buffered with 375 mg/L of baking soda. For euthanasia, triple-dose it. It takes a long while, especially for large animals, and be sure to confirm the death by freezing - the last thing you want is the animal to wake up again after being disposed of.

 

[MikeCurtin]

My recommendation is a slow cooldown, possibly in the fridge. This shouldn't cause the ice-crystal problem, but will put the animal to sleep. From there, you can try various things, such as the freezer, with less qualms. Honestly, I'd recommend double-pithing (inserting a sharp probe into the brain via the base of the neck, and quickly "scrambling" it, then doing the same for the anterior spinal cord) after deep refrigeration, but that requires even more skill than cervical dislocation, especially on small animals.


So, IMHO: Fridge first, then freezer. It may not be 100% like anaesthetic overdose, but the use of the fridge will make it the most palatable method.

From everything I've read, I would have to agree with this method...still sucks, but seems to be one of the better methods.

 

[geckogrl6]

I agree. From what I had heard, a slow cool down is the best option if/when a vet is not available. I have the same issues the OP had with neck breaking, beheading, etc. I do tend to take an intermediate step and reduce the temp first to room temp (ie- turn off the UTH) overnight, and then try to find a cool spot in the house for a couple hours before the fridge. I also tend to move them from a slightly warmer to a slightly colder part of the fridge if possible.