No animal wishes to be eaten, and it will instinctively seek to avoid death, but necessarily for the food chain, it will ultimately not be able to overcome its fate. Whether it is taken down early by a predator or at the end of a long natural life is of no major consequence, because death is inevitable and is not a cause for worry provided the species can sustain itself. There are certainly more and less humane ways to keep, house and kill an animal, though. These are the shades of grey that you don't take into account.
Back on topic, almost every animal knows and embraces the act of sex. Typically they're drawn to their own species, but frankly, a dick is a dick and a hole is a hole (as long as the size is compatible). It doesn't change the experience tremendously for them if both participants aren't the same species, and I don't honestly think they mind. What can be highly problematic is if sex is tried outside the animal's natural breeding cycle. They may not be physically prepared or equipped to deal with it, and this can result in panic, injury, death. Animals have courting rituals between themselves to help signal each to each other how and when to procreate safely. A lot of so-called "zoophiles," who purport to have a relationship with animals, ignore this elaborate dance and just fuck whenever. However, if the proper care is taken to recognize the animal's signs of readiness and only act during this time, and to take the proper care afterwards (since some disease can be spread between man and beast) then I don't see where there's any real issue.
