How to Treat Lice in Cattle

Lice often infect cattle in the winter months. During the summer environment, self-grooming as well as shorter and thinner hair keep louse numbers low. Physically, lice are small but they can exist on cattle by the thousands. Five main species of lice are found in North America. Four of these feed by sucking blood and are the longnosed cattle louse, shortnosed cattle louse, little blue cattle louse and the cattle tail louse. The fifth species is considered a biting louse called the cattle biting louse and feeds on the skin of cattle.

Instructions

  1. Inspection and Treatment

    • 1

      Determine the cattle have lice. An infested animal will rub on fence posts, trees, water troughs or other objects to relieve itching and irritation from feeding lice. This results in damaged fencing, bruising and scraping to the animal's body and large areas of bare skin. Anemia can result in severe infestations due to blood loss from sucking lice. This can lead to low resistance to disease, reduced weight gain and low tolerance to stress due to weather or shipping. Heavy infestations can also cause pregnant animals to abort.

    • 2

      Inspect the cattle by parting the hair a few inches and looking for the presence of eggs. Hair coat may appear matted due to the attachment of eggs. Skin reactions occurring from biting lice may cause the hair to become loose and fall out during inspection. Places on the animal to check include the neck, wither (point of shoulder), shoulders, midback and tail head (top of tail). More than one species of cattle lice can exist on one animal. Lice feed with their head down and abdomen pointing up. Record the amount found per square inch. Less than five is considered very slight while more than 50 is very severe.

    • 3

      Treat cattle with an insecticide. These treatments take the form of a dip, spray, pour-on, spot-on, injectable, dusts and back rubbers (animal rubs against and medication disperses). Each treatment requires adhering to label applications and is effective against various parasites. Consult with a veterinarian to help with appropriate product choices and application instructions. In any case, most products will not effect louse eggs. Lice which hatch after the first treatment can re-infest the cattle. Retreat the cattle two or three weeks after the initial treatment to kill lice before they can lay eggs.

    • 4

      Vacate infested animals from current premises. Lice spread from animal to animal when they are in close proximity to each other. Lice eggs may fall onto bedding or be rubbed off while the animal is scratching. Removal of the animals will prevent reinfestation from the contaminated area. Do not allow treated and untreated animals to co-mingle. Treat vacated area with an insecticide or leave empty for a minimum of 10 days.