I have buried some, and I have burned some (cremation). If it's infection, my preference is the burn pile, no worries of bacteria making something else sick. I would also do that if it was viral. I always have a large pile of limbs and yard stuff, so normally that is convenient for me. I have also kept them in the freezer for a time on occasion. When you have an animal euthanized by injection, the meds remain in the body and can adversely effect an animal that eats them, so bury deep if you go that route.