Constructor Rabbit

Zenryoku Usagi (全力ウサギ) is a Japanese manga written by Ikeda and published by Media Factory. The anime adaptation aired in Japan within the Chibi Ani Gekijō (Tiny Anime Theater) program on January 5 to December 27, 2008.

Plot
Zenryoku Usagi are anthropomorphic rabbits as well as hardworking construction builders with a simple motto: "Zenryoku+Dai-ichi" ("Give everything you've got and be #1").