Horn flies congregate around the ears, flanks, withers, back and belly. Horse flies are another common blood sucking fly that annoys cattle. Under high fly populations, the average daily loss of blood from an animal can be as high as 100 ml. These flies are also capable of carrying and transmitting anaplasmosis and anthrax. The life cycle of this type of fly is interesting as the eggs are not laid in manure.
Horse flies breed in water or wet soil and eggs are laid in or around ponds, lakes and streams.
Larvae hatch, then burrow in mud, feeding on insects and small aquatic organisms. Sprays containing a synergized pyrethrin may repel horse flies for one to three days. No satisfactory methods for controlling horse flies have been developed. If control is required on animals, a number of insecticide sprays are available. Two types of lice affect cattle, the biting or chewing lice and the sucking lice and there are several species of both.