No cows and horses spawning in realm.

Ever since the latest update, in addition to no slimes spawning in swamps any more, cows and horses have stopped spawning in my Survival Normal realm. I've searched in a 500 block radius, through a variety of biomes, around my base over the course of a few days, and have only managed to find one cow and a previously saddled horse that someone lost. And I haven't seen many pigs, either. Sheep and chickens are not plentiful, but still present.