The mulgore was part of an April Fool's joke by Blizzard Entertainment as to the supposed release of the tauren marine for the terran faction in StarCraft II. The mulgore was where they would be produced at.
Given its status as part of an April Fool's joke, the Mulgore should not be taken as canon.
StarCraft II: Tauren Marine. Accessed on 2008-01-04