Cattle
Cattle who are being fattened for slaughter are branded and their horns and testicles are cut out - all withOUT painkilers. They often don't get appropiate vetrinary care, since they are just going to be slaughterd anyways. So things like lameness, which affects almost half dairy cows, and chronic ithiness, which affects nearly one-third of pigs, are aften untreated. After all, lameness and itching don't effect that hamburger of yours.
Up to three times a day, dairy cows get electric machines hooked up to their massively swollen udders. Cuts and injuries to thier udders are common - and so is mastitis, a painful infection. The pus, blood, and scabs, plus hormones and antibiotics, all end up in that milk mustache. Enjoy
After birth, male calves are torn from their moms, causing fear and stress. Then they're shipped to veal farms, where they spend the rest of their lives on short chains in filthy, narrow stalls where they can never turn around or lie down comfortably. They're unable to move around, kept in isolation, and fed nutriend deficient food so that their flesh will be pale and tender when served to unenlightened "gourments".