Core Keeper

The "cattle" are friendly creature that spawn in the sub biome "meatdow" it can be found randomely in the dirt biome or in the azeroth wilderness. To feed them you just need to have any grow plant like hearthberry or glowtulip. Just like in minecraft the "sheep" and "cow" that you find in this biome will follow you if you have a heartberry in you hand. And you can feed her by right cliking or dropping on the ground the food source.

Note : after the paws and claws update they had some reserve to auto feed the animals, this doesnt give the achievement you need to manualy give here the food.