Participants in the Interagency Bison Management Plan have suspended plans to ship bison to slaughter from Yellowstone National Park until a federal district judge rules on a challenge filed by wildlife advocates last week. Park Spokesman Al Nash says about 380 bison were hazed into the Stephens Creek facility on the north end of the park and are being tested for brucellosis. Those found to be infected were to have been shipped to slaughter. Brucellosis can cause wildlife and livestock to prematurely abort their young and it is feared the bison could pass the disease along to domestic cattle if allowed to intermingle on private land. Nash says about a third of those animals tested have been positively identified to be infected. Those not infected would be returned to the park at green-up in April.