This Mod works simply. Whenever a world-spawned animal is killed, it will respawn after a while in a location close to its death. If you don't want the animal to return, have the Amulet of Souls in your inventory.
FAQ:
* Does it work with animals from other mods?
Yes, however, if the creator does not define the entity as an animal, problems may arise.
* Does it work with aggressive entities?
No.
* If the chunk is not loaded will the animal respawn?
Yes.
* Do animals generated by breeding respawn?
No, only naturally generated animals.
Settings:
Local: your_game_directory/config/respawn_animals.json
* days_for_respawn_animal: defines how long it will take for the animal to respawn (0.5 is equal to one night or day).
* mobs_black_list: put here all the animals you don't want to respawn.