The subject you referenced involves bestiality, which is widely considered animal abuse and is illegal in many jurisdictions.

Physical pain is almost always accompanied by a change in behavior. A cat urinating outside the litter box isn’t being "spiteful"; she might have a painful bladder infection. A dog suddenly snapping at the mailman isn’t "dominant"; he might have undiagnosed hip dysplasia making him feel vulnerable.

Take the case of "Luna," a five-year-old German Shepherd. Her owners wanted to euthanize her because she attacked the vacuum cleaner so violently she broke a tooth. The previous vet said, "She needs obedience school."