Aalborg zoo explains that if people have animals that need to be removed "for various reasons", they can bring a maximum of four small species at once. The animals are euthanised by trained staff and then used as food.
Before you ask, they don’t do collections and they have to be your pets.
Less waste? They euthanize them first. I’d give them my body after I’m done with it, but it’s probably not going to be safe to eat