If you want to add basic animals to your world, I recommend this mod. The animals seem less janky than those from mobs_animal, and they have more unique behaviors. In my opinion, their textures and models also look nicer. The head movements are a nice touch. However, some of the animals could use more variety in their idling sounds. Another issue I have noticed is that the animals constantly jump while standing on snow layers, but this will probably be fixed eventually.