The people who wrote the constitution and declared all men to be created equal owned slaves. Most vets think that because some cows are in fields during the spring and summer and up to their ankles in shit in a shed during the winter that there is no ethical problem gassing baby chickens or keeping pigs locked in crates in dark sheds for weeks on end. They'd weep at the thought of a dog having it's tail & testicles chopped off and teeth cut/ground down as a baby (all legally done by untrained farmers and without anaesthetic). Yet they'll pay for this to be done to pigs in their name. They'd take to the streets to prevent dogs being crammed into trucks, covered in their own shit and shocked with electric prods down a corridor towards cries of fear and the smell of blood. They'd never allow a dog to be shot in the face, hung by it's ankles and stabbed in the throat at two years old. They'd never let a cat be tied by it's head to a post, have a finger stuck up it's ass and then stick a metal rod in their vagina, take away the kittens immediately and repeat the process so that the cat is perpetually lactating and/or pregnant. They'll happily pay for all of the above to happen, three times a day, to pigs and chickens and cows without thinking twice. It's cognitive dissonance in it's purest form. You also have to keep in mind that a lot of, but by no means all, large animal vets don't really care about animals that much. They'd find someone showing affection to a dog, never mind letting it in the house, to be strange. They are just there because they're the smart children of a farming household, not out of some love of animal per se. You can't judge them any more harshly because they are vets, they have been subjected to the same industry propaganda as everyone else for their entire lives.