Remember:
humans != rats / mices
rats != rats
mices != mices

Pentobarbital readily crosses the placenta resulting in fetal depression in pregnant animals. Death of the dam normally precedes the death of the fetus. In 1 study cardiac arrest in lambs was delayed for as long as 25 minutes beyond the death of the dam. Similar observations in mice demonstrated that death of the fetuses could only be achieved by the use of doses well in excess of those normally required for euthanasia.

Any laboratory rodents with altricial young, such as mice and rats, must be differentiated from rodents with precocial young, such as guinea pigs. Precocial young should be treated as adults.

Intraperitoneal injections of 70% to 100% ethanol may be an appropriate method of eu- thanasia for adult mice when physical methods are not desired or other euthanasia agents are unavailable. The use of ethanol in mice < 35 days of age is questionable due to the long latency to death. Ethanol is not recommended in larger species such as rats due to the large volume required to induce death.

Manual cervical dislocation is acceptable with conditions for euthanasia of small birds, poultry, mice, rats weighing < 200 g, and rabbits when performed by individuals with a demonstrated high degree of technical proficiency.

Ethanol is acceptable with conditions as an agent of euthanasia for mice 35 days of age and older, but is unacceptable as an agent of euthanasia for larger species.

Variability in behavioral responses to CO2 has been reported for rats and mice, pigs, and poultry.

Rats and mice allowed to travel between chambers containing different gases spent most of their time in the control chamber (containing air), but preferred a hypoxic chamber (containing Ar) to a chamber containing CO2.

Decapitation CAN be used to euthanize rodents and small rabbits in research settings 🤦‍♂️❗️❗️❗️

If we apply such research to humans, we would have a lot of 💀 like Dahmer ...
@CannibalTelegram64

Animals studies are not fully applicable to humans