@Mr Stillwater,
My only experience with hamsters, the cuties, is that my cousin's son lost one in their car on some long trip. Sad ending.
On guinea pigs, I was a lab tech in my early day, not an evil lab, and I carried one around in my lab coat pocket. I'm sure that's a no-no now. That was probably the start of my from thence lifetime allergies. Whatever, I liked them. No, I never "sacrificed" one. Their sera had anti-human immunoglobulins and was useful in those earlier immunology days (a short explanation) re collagen disease research. The guinea pigs tended to live their lifespan, far as I knew.
Of course, that was then.
HOWEVER, I once saw, back in school, a giant quonset hut full of guinea pigs at Olive View hospital, at that time mainly a tb facility. Test pigs. Weird, creepy, horrendous, every one of them cute.
TB was still a big threat back in '61. My aunt's first husband died of tb, and she'd spent years herself at a sanitorium. And that was around the time I'd just finished reading Sinclair Lewis' Arrowsmith. Still, that hut remains in my mind.