It's a breed of dog. It's actually called a Louisiana Catahoula Leopard dog: Here's a photo:
Obviously not the same individual as in my first post (dog with prostatitis and pyelonephritis) but the same breed.
Well, the same guy as in my first post came in with a massive, painful swelling that had come up over about 3 days, located under and lateral to the left eye.
Opened his mouth and there it was: a draining tract just over the large, 4th premolar (carnassial tooth, 3-rooted tooth in the dog and cat).
Diagnosis = tooth root abscess. For similar case, see previous post with dental radiograph. Same diagnosis, different tooth.
For all you vets and non-vets out there: if you can't find the infection, look in the mouth!
For more info on the Catahoula: http://www.catahoulas.org/catahoula.htm