Pet Rats/One of my rats killed the other.
In total my fiancee and I had 4 rats, my two and his two. The sets of two lived in separate cages at our houses, he had the rats in question Daisy(black hooded) and pichu (cinnamon hooded) Daisy always had an aggression problem when it came to men and chewed holes in the cage to escape and run on the floor. Today i got a disturbing call from my fiancee, who claimed "Daisy killed pichu, her face is gone." He left to take a shower (keep in mind neither he or his Nana heard any screaming from the rats) when he came back, Daisy was sitting alone and pichu had half of her face ripped clean off, her skull and jaws were clearly visible. My fiancee decided it was best to release Daisy outside and let nature have it's way with her, instead she bit his hand and ran into the outside world. My question is why would she do such a brutal thing to pichu? I've heard it is very unnatural for a rat to kill a cagemate so maliciously? Please answer soon as I'd like to get these sad thoughts from my mind and to feel peace for pichu.
I know this was a shocking tragedy for you. I sympathize. Pichu was not killed by Daisy. This just doesn't happen. I'm sure Pichu died on her own. Sudden death can occur from heart failure or a stroke, which can even be caused by an unidentified internal tumor. I have had that happen.
It is pretty common for rats to eat part of a dead companion. They understand that it is just a body and that the spirit of their friend is gone. I like to compare it to primitive human cultures where they ate parts of people, especially family members, to honor them.
You need to try to find Daisy otherwise she is going to die a nasty death outside. Perhaps you could put her cage outside in the hopes she will come back and get inside when she gets hungry and thirsty. In or near the cage place some food that she canít carry off, like some soft food on a plate like baby food or yogurt.