One time, a corsican ram down in Texas. He smelled worse than the average sheep, and when we caped him, found his hair pulled out in clumps and his hide & good part up the hair covered in a stinky, gritty, greasy ooze.
Both the guide & taxidermist said they had no idea what it was but both recommended against eating him or messing with the cape. Ended up doing a European and the carcass went on the burn pile.
To this day I've never seen anything like it. On the hoof and to all outward appearances before I arrowed him he looked healthy, but I wouldn't have eaten a bite of his backstraps on a bet.