When chickens ate medicated feed containing 1.5 to three pounds of betaine per ton, intestinal invasion by the parasites was 50 to 90 percent lower than in birds not given betaine in the feed, and parasite development was significantly hindered. So there's no reason to send the cow to slaughter. That's the latest word from researchers studying this new parasite, discovered and named by ARS researchers in 1988. Since then, N. caninum has been pinpointed as a major cause of dairy cattle abortions in several countries, including the United States, the Netherlands, Australia and New Zealand. In California, more than 25 percent of all dairy cattle abortions in the past five years were caused by N. caninum .
Abortion can occur at any time during gestation.
Sometimes calves are born weak and paralyzed and die within a week. Some heifers are born infected and free of symptoms, but subsequently give birth to infected calves. Cows that become infected and abort a calf remain clinically normal. ARS researchers have developed a test to diagnose neosporosis, but no vaccine or treatment exists. In 1992, a Belgian scientist first identified and named Arcobacter , a close relative of Campylobacter .