They are most abundant on the top of the head and on the neck, shoulders, back, and rump. They crawl about freely, irritating the skin with both their sharp claws and their short, chewing or sucking mouthparts. They hatch in about 8 days and 3 nymphal instars develop over the next 18 to 21 days. Adult females, ready to lay eggs within a couple of days, outnumber males and live about 42 days. They lay about 30 eggs at the rate of about one egg every 36 hours.
Cattle lice thrive at the normal surface temperature of the host's body.
A variation of only a few degrees in either direction can be lethal. Infestations are usually light in summer and heavy in late winter and early spring. The best control is prevention of an infestation. New cattle should be examined thoroughly for lice before being introduced to a herd. Properly labeled pour-on insecticides give quick and effective control.