I have one of those weirdos that constricted without biting. That WAS rather strange. She's only done that once, so far, though
I have another one that drives me crazy, though. OMG, I can't watch her eat. (they never see me watching, I peek around the corner)
She will strike. Then let go and sniff all around. Then she proceeds to try to eat it anyway but the right way. Backwards. SIDEWAYS (no kidding). Leg first. I've seen her do all of that. She will struggle and struggle.
Trying to remove it and getting her to start over doesn't work. Lining it up just right so she grabs it by the head doesn't work. She lets go and then starts over anywhere BUT the head.
And yes, the FT rat is warmed up appropriately. None of the others do that. Ever. I even tried warming the head more then the rest of the body. Makes no difference.
I literally have to walk away and not watch, LOL.
She always gets it eventually. Usually she gives up chewing the foot, middle or butt and goes to the head. But I swear she works so hard, it just kills me...