closely to make sure they are labeled for tick control. Cattle lice are found throughout the U.S. in several different species. Some suck blood while others cause scabs on the skin... from feeding on the external skin layers. Lice are commonly found in larger numbers in the cooler months, even winter. They cause skin irritation to the point that cattle will rub... the hair off of areas, which results in bare patches of skin. Lice are effectively controlled through systemic pour-ons, sprays and dust. Reference: Progressive Cattleman magazine...