Zenryoku Usagi

Zenryoku Usagi are hardworking construction builders — who happen to be rabbits — with a simple motto: "Zenryoku+Dai-ichi" ("Give everything you've got and be #1.") The animated shorts were aired in Japan within the Chibi Ani Gekijou; (Tiny Anime Theater) program on Friday or Saturday mornings, depending on the station. Ikeda and Media Factory have created two books and numerous spinoff goods featuring the characters.
(Source: Saikin Anime Jouhou)