About Tribbles
A small animal characteristically soft, furry, and pleasing to most humanoids (with the exception of Klingons). Tribbles give off a soft purring sound that is soothing to many. They are also asexual, born pregnant, the only determinant of birthing being how much food they consume. Tribbles originate from Iota Geminorum IV and were first known to humans in the early 2150s. The tribble homeworld was destroyed in the 23rd century by Klingons who considered the tribbles an ecological threat. Tribbles were brought forward in time to 2373 with DS9 and thus reintroduced.
Tribbles appear in TOS:2.042: "The Trouble with Tribbles", DS9:5.503: "Trials and Tribble-ations" and TAS:1.105: "More Tribbles, More Troubles." References are made to our furry friends in ENT: "The Breach", DS9 "The Nagus" and "A Man Alone."
From StarTrek.com