Plaguehound

From WoWWiki

A level 55-56 darkhound found in the middle of the Eastern Plaguelands.

Plaguehounds as a Quest Objective

Tirion Fordring considers them a nuisance and wants them exterminated. 5 Plaguehounds must be killed, along with 20 Plaguehound Runts and 5 Frenzied Plaguehounds, for the quest  [56] Demon Dogs