Lice Control on Beef Cattle, 1976

Single treatments were administered to cows and heifer and steer calves between January 30 and February 4'76. The “spot-on” was applied with a syringe on the top line, posterior to the withers. The injectable was placed intramuscularly in the rump. Ten animals from each treated group were inspected for lice, except when fewer than 10 head were available. Lice inspection areas were the entire head and three 6-in hair parts in the brisket, neck, backline and rump-tailhead. Viable lice were determined post treatment by microscopic examination. Large numbers of lice on the back and rump (= hind portion) were predominantly B. bovis. Those present in large numbers on the head, neck and brisket (= front) were S. capillatus. L. vituli were chiefly on tfie front of the animals but usually were less than 10/inspection area.