freezing mice......humane question...well lots of

[CrazyHedgehog]

Originally Posted by Cazador

I won't offer an opinion on the most humane way to kill them because I think it's debatable and largely a matter of personal preference.

I do understand that, but would still appreciate your oppinion, maybe send me a private message if you feel it may contradict others?
Or maybe I should rephrase to how I definately shouldn't kill them, things to avoid... and see what options I am left with...

[Cazador]

PM is on the way, but this topic isn't my area of expertise. It's just another opinion .

[abcat1993]

Now that I think about it, if I had to pick up a mouse and kill it (by any method listed in earlier posts) I would probably feel sorry for the thing and put it back with it's mom. On the other hand I might just be too scared to take it away from it's mom in the first place (I've been bitten several times pretty badly from my gerbils).

[CrazyHedgehog]

I know....I haven't even bought a single mouse to start yet, but still I am worried that we are going to end up with 400 'pet' mice!!!

[KITKAT]

OK... a clarification is needed I see!

I was not speaking figuratively.

There are actually four terms for how animals thermoregulate.

Ectothermic = an animal that gains needed heat from the environment

Endothermic = an animal that gains needed heat from physiological processes

Homeothermic = an animal that seeks to (needs to) maintain a constant body temperature.

Poikilothermic = an animal whose temperature naturally varies.

Adult mice are mostly endothermic and homeothermic. They are capable of keeping a constant body temperature by utilizing their own physiological processes. Only in extreme temperatures do they resort to insulated nests to prevent freezing.

Newborn mice are mostly ectothermic and homeothermic. In other words, they need a constant body temperature to remain healthy and alive, but they cannot maintain that constant temp by means of physiology - they must rely on the parent mouse, and an insulted nest to maintain the needed internal temperatures.

Remove those environmental factors, and the newborn mouse will die. The speed at which it dies will depend on the environmental temperatures to which it is exposed. That speed will also be hastened by lack of body mass, lack of body fat, and a physiological thermoregulation process that is not complete until the baby mouse is more mature.

One cannot be sure what the newborn mouse feels as it freezes, but the process LOOKS similar to that experienced by a reptile going into brumation. The heart and respiration gradually slow, the movements slow, and the newborn mouse appears to lack mental alertness as the temperature drops. There is no shivering, the squirming is not violent or frantic in appearance, and the processes of the mouse just slow down.

Due to lack of body mass, the newborn mouse does not last long when exposed to freezing temperatures, and the entire process is usually finished in a few minutes.

Originally Posted by Cazador

Just to be clear, I think Kitkat was speaking figuratively since all mammals are warm blooded (endothermic). Small organisms have more surface area (skin) per unit of mass (volume), so they gain or lose heat more rapidly (like reptiles) than larger individuals do. Pinkies also lack hair and have minimal fat, so they have less insulation. This allows them to die and freeze quickly.

I won't offer an opinion on the most humane way to kill them because I think it's debatable and largely a matter of personal preference.

[suzoo]

You guys are way too nice! And I admit, I do have a few pet mice, but if I get attached to one in paticular, I raise it as a breeder. I have never had a pinkie or fuzzy stay alive more than a few minutes in the freezer, and if one of them bites me, they are thrown on the floor (or against the wall) by automatic reaction to being bitten. I play and love my breeder mice, but I have had experience in overpopulations, and even cleaning cages every day THEY STINK! So putting the babies in the freezer does not bother me, and I leave one to three on mom to grow.
Suzoo

[CrazyHedgehog]

Ok, I think I am happy with the pinkies freezing in tissue paper.....

but on to bigger mice, I found a great article on the effects of C02 and how to make home made gas chambers, how to make cheap C02...

Small animal euthanasia at home

[Stefan-A]

Originally Posted by Cazador

Hi all,
I just wanted to sort of discourage the carbon monoxide (CO) idea because it has a really high affinity for the iron molecule in hemoglobin, and essentially binds irreversibly. That means the CO will remain in a red blood cell until the cell dies, and they normally have an approximately 60 day lifespan. Even if all the red blood cells ruptured during freezing, the lack of a functional circulatory system would prevent its release from within the mouse. There is also the distinct possibility that you might euthanize yourself while administering the CO to the mouse. Keep it safe,
Rick

Feel free to correct me:

The impression I got from last week's chemistry class (I study sustainable development and the course is very ecology/biology oriented, so much of the focus has been on carbon and oxygen), the body uses iron (certain animals use copper) in hemoglobin to bind and transport oxygen and CO is attracted to that oxygen. The reason is that CO is unstable and by attaching itself to that O, it creates CO2 and becomes stable. It doesn't stay CO, it becomes CO2 in the body. Disclaimer: it wouldn't surprise me if this explanation was wrong, I wouldn't expect a chemistry teacher to know the first thing about biology. Most explanations suggest that CO just replaces the O in the protein and none of them seem to consider it a direct health hazard when consumed (as opposed to inhaled). According to wikipedia CO is even used to treat seafood and beef?

[abcat1993]

But who knows who can change Wikapedia.

[Stefan-A]

It's not just in wikipedia.