How were the animals rewarded for their hard labour animal farm

Well, the farm was supposedly "communist", so therefore, the animals would have been reward with food and other resources but instead, they weren't really rewarded.. the pigs were the ones who were rewarded rather than the other animals.

and instead of rewarding them, they even send boxer (the hard-working horse) off to the butchers to be fed to dogs in order to obtain some alcohol.

if this is a prompt, i'd go against it.