Lice Treatment for Horses and Livestock

October 3, 2011 (published)

Lice are parasites that affect horses, cattle, sheep and goats. They are common in the late winter and early spring. There are actually two species of lice that affect livestock: biting and sucking lice. The most common sign of lice is hair loss that is due to rubbing and scratching of the hair. The neck seems to be the first area affected but the whole body can develop hair loss and also if the lice are not treated, sores and bacterial infection can develop secondary to scratching and rubbing. Lice can be diagnosed fairly easily if you know to look for them as they can be seen without magnification. A flea comb used for detecting fleas on dogs will pick up the lice. Treatment of lice requires topical use of an approved insecticide every 2 weeks for two to three treatments. Treatment followup at 2-week intervals is critical because eggs are not killed by the treatment and if follow up treatment is not performed, the life cycle will not be broken and the disease will continue.

It is important to make sure the product is approved for use in the species you are treating and you have to be careful because there are very few products approved for goats, particularly dairy goats. The entire herd must be treated because lice are very contagious. Also, all tack, blankets, and other materials used on the animals, such as brushes, must be treated every 2 weeks at the same time as the animals. Oral ivermectin or injectable can be used on livestock but must be used every 2 weeks and does not kill biting lice. Topical lime sulfur dip is safe and effective on most animals. The environment should also be treated with a flea spray approved for cats, as it will kill lice.

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