The theme music to this short is a "throwback," being the series' 1937-1938 theme rather than the usual 1938-1941 version.
The bullfight is being broadcast on KFWB radio, a nod to Warner Brothers.
At the end, Porky morphs into Oliver Hardy.
The bovines cheering on the bull are a nod to the popular advertising character of the era, the contented dairy cow that gave good milk. It was used by Carnation and Borden.