Andromeda Gamma Epsilon

The Wirrn Breeding Colonies were a group of planets in the Andromeda Galaxy controlled by the Wirrn and used for breeding, although on account stated the breeding colonies were on Andromeda Gamma Epsilon. (PROSE: Doctor Who and the Ark in Space) Though the Wirrn lived most of their life in space, they needed terrestrial planets to reproduce so they could incubate animals — usually senseless herbivores — limiting their technological progress.

When humans expanded into Andromeda they started taking the breeding planets and, after a thousand years of fighting, eventually drove the Wirrn from the galaxy. (TV: The Ark in Space)