Midrash for Chullin 159:45

הני עזי דבאלא מהו לגבי מזבח

renders [Teo as] 'the wild ox', it is certainly a species of cattle, whereas R'Jose maintains, since it is reckoned together with the other species of wild animals it is a species of wild animal; but these [forest goats], according to all views, belong to the species of goats.

Sifrei Devarim