I always assumed that the sacrifice method depended on the research.  You might liquefy them in a centrifuge, or pith them with a probe, or asphyxiate them in pure gaseous nitrogen, or flash freeze them in liquid nitrogen.  Whatever makes sense for the study.<p>But if the animals in question are not part of the study at all, I don&#x27;t see how it matters much.  Maybe there&#x27;s a little mouse guillotine.  Maybe one person on the team owns a reptile pet that is very well fed.  The reason why rodent models are used in the first place is that they&#x27;re mammals, easy to care for, breed, and handle, and no one really cares if they die by the millions.<p>If they were outside the lab, they would likely get poisoned or crushed by snap traps.  (That&#x27;s better than what a cat would do.)  Cuteness won&#x27;t save you from my wrath if you eat my food and then poop in whatever you left behind.  At least the ones that died in the labs had <i>real</i> jobs, instead of living hedonistic freeloader lifestyles inside someone else&#x27;s couch.