I have milked a horse, and let me tell you she wasn't happy about it. We had to get the colostrum into her baby (whom she had rejected). She was sedated and there were four people helping (on top of the acepromazine, mind you). We had her blindfolded, lip twitched, someone was holding a skin roll on her neck, we had her pinned up against a wall and some one was pulling her tail and holding up one of her legs so that she couldn't kick me. I managed to get 6oz of colostrum for the baby to drink, I nearly missed losing my face and vowed never to breed that mare again. Have you ever seen how small a horses teats are? But the foals titres came out normal, so it was all worth it.