Banrai no Hekatoncheir

The manga centers on Tokio Rokuō, a boy hunter who has nevertheless lived with and loves animals. To save an animal, he takes a fall from a cliff. When he wakes up, he finds himself in a completely different world filled with demi-humans. Now, with a newly strengthened body, and his skill in animal handling, he must find a way to survive in his new world.

(Source: Anime News Network)