Hespic

From Tardis Wiki, the free Doctor Who reference

Hespic was a planet known for its amazing cuisine. Not technologically advanced, this rural world nurtured a range of exciting vegetation (some of which was deemed rude), that was for a very brief while accelerated by the arrival of a creature that resembled a cross between a chicken and a sheep. It exuded some kind of super-fertiliser from its constant flatulence, probably due to its diet. It was captured by the Eleventh Doctor, Amy Pond and Rory Williams. They moved it to another planet where it could freely roam, helping stimulate agriculture. (COMIC: Grow Your Own)