Date of this Version



EC 73-1907

Extension Service . University of Nebraska-Lincoln College of Agriculture Cooperating with the U. S. Department of Agriculture and the College of Home Economics


Extension Circular 73-1907 is about internal parasites in cows and how they affect cattle production.

Internal parasites continue to be one of the major problems confronting cattle producers. In 1965, the United States Department of Agriculture estimated that internal parasites in cattle caused an average annual loss of $161,678,000. The internal parasites responsible for the annual loss are listed below.

Anaplasmosis. .$ 36,001,000

Coccidiosis . . . .14,569,000

Worm Parasites .100,046,000

Liver Flukes . . . 3,022,000

Trichomoniasis .. 8,040,000

In cattle the effects of internal parasites will be well camouflaged. However, additional feed will be required to reach market weight. Parasitologists have estimated that subclinical infections of internal parasites may reduce weight gains in cattle as much as 10 to 20 percent. Contrary to popu lar opinion, worms do grow best in healthy, well-fed cattle.