One Piece - episode 84 - 20 Oct, 2001

Nami asks Chopper to join the crew, but he isn't interested. Kureha tells Nami that Chopper is a reindeer who ate the Human-Human Fruit and some of what was his background. After realizing the abilities that Chopper has, Luffy is eager to make him join the crew. (Source: Wikipedia) Alabasta saga: Drum Island arc: (7/14)