The steroid scandals have hit the rodeo circuit, but it's the bulls - not the cowboys - who are being tested.

Rodeo stock contractors are said to routinely use anabolic steroids to bulk up their 1 ton bovine athletes. But the steroids have some unwanted side effects. The bulls get bigger and more aggressive, and that's considered good, but some bulls become sterile, cutting their value as breeders. Some say this alone has limited the use of steroids in bulls.

The Professional Bull Riders (PBR) group isn't taking chances, though. It announced a testing program for top bull winners. Stock contractors who violate the no-steroid policy will be fined and sanctioned.