I hurt cows when feeding the final wheat of a stack. No matter what I do, I cannot avoid it for some reason. The cow always gets hurt wth that single piece of wheat, and the wheat itself is wasted because the cow's love mode immediately ends after getting hit. xD

Also, when milking cows the opposite happens. The first few buckets harm the cow (I do get the milk), but the last bucket does no harm and works as normal.