Lice on Alpacas and Llamas

Lice infestations are best treated with Sevin dust and Cylence pour-on.

Lice (singular: louse) are insects that can be seen with the naked eye if you look very carefully. Find a spot along the topline and part the fiber down to the skin. If you see little little-colored specs that look like danfruff -- those are lice. Lice are flattened and possess no wings. They are very host-specific and do not tend to leave their preferred animal. That is, lice do not tend to jump from one species to another. Lice spend their entire life cycle on one animal.

Spread of Lice

Transmission of lice is by direct contact with an infested animal. Unlike fleas and ticks, lice do not persist or travel in the environment. Grooming instruments may, however, serve as a source of transmission. Lice lay eggs (termed nits) on the hair shafts. The life cycle takes about 21 days to complete.

Spread of lice is most likely to occur with close body contact at shows, sales, and during mating, transport and lactation. Contaminated grooming equipment may also provide a source of infestation, but communal rolling areas are less of a risk.

Detecting Lice

Signs of lice include rubbing the affected areas, dandruff, and fiber loss in large patches. Detection of lice infestation is usually made at shearing time and usually only found in heavily infested camelids. Numerous white eggs are found firmly attached to the fleece 5 to 10 mm above the skin, particularly on the flanks and lateral thorax caudal to the elbows When the fleece is parted, 1 to 1.5 mm long white and light-brown adult lice can be seen moving across the skin. Generally less than 5 % of each herd is heavily infested.

Life Cycle of Lice

The life cycle intervals of the louse are as follows: adult lice copulate, then the female deposits fertilised eggs onto hair fibers. The eggs hatch within 1 to 2 weeks to give rise to a first stage nymph. The nymph has 3 stages of development as it matures to adult size. Maturation takes 2 to 3 weeks. The life cycle can be completed in as little as 3 to 5 weeks. Adults may live on average from 30 to 50 days. Studies have shown that lice shed into the environment will all die within 5 days. However eggs can take up to 8 to 12 days to hatch, but the unfed, newly emerged, first stage nymphs live no longer than 12 hours.

From these findings, it is seen that the risk of transfer via inanimate objects such as grooming utensils, blankets or harnesses is quite high. These items should be disinfected regularly as a precaution against unwanted transfer of lice. In the case of housing or bedding a 14 day spelling period would be sufficient to ensure absolute protection against reinfestation.

Weather-Related Infestation

In areas with mild winters, lice invade animal fleece for warmth, and what could be warmer than nice alpaca and llama fleece? So intervention in early Autumn when the nights start turning cool around 65F degrees is recommended.

Treatment

Treatment may be a topical dust or a pour on medication, depending on whether you are treating for sucking or chewing lice. Treatment for the sucking lice is injectible Ivomec SQ, However, Ivomec is not effective for the biting lice.

Treatment for the chewing lice is 50% Methovychlor (Marlate at WalMart), 5% Sevin dust, or 50% Rose Dust, (Captains at WalMart) applied topically. Chewing lice may also be treated with the pour-on, Cylence, at a rate of 1 ml for crias, 2 ml for 100 lbs, and 2 ml for 4 lb. Treatment for chewing lice should be every two weeks.

This page was last updated on September 29, 2008.