Lice

8.5 LICE

Lice are described as biting or sucking types, depending on their mouth parts and method of feeding. Both types can cause problems in livestock. They seem to affect animals that are malnourished, and young animals. In general, lice that infest one species of animal do not infest other species of animals.

Lice live amongst the hair. They bite the skin or suck blood when feeding. This irritates the animal. Animals with lice spend much time rubbing and scratching. This damages the hair and wool. The white eggs of the lice, called nits, may be seen by parting the hair / wool and looking carefully near where the hair enters the skin.

 In pigs, sucking lice are usually seen around the head, neck, and legs. They cause the pig to be restless and spend much time scratching. The pigs spend less time eating, and become thin and unhealthy.

 In buffalo, the eggs of lice are seen stuck in the hair of the animal. However they do not seem to cause many problems except for young or malnourished buffalo.

 In sheep with thick wool, heavy infestation with lice damages the wool.

 In chickens, biting lice cause lowered weight gain or egg production.

 In camels, llamas, and alpacas, lice cause itching and excessive dandruff.

Biting Louse Lifecycle: Adult lice live mostly on the animal. They spread from one animal to another by direct contact or through infested equipment. In general, adult lice cannot survive for more than one week off the animal.

Symptoms / Diagnosis: Itching, scratching and damage to skin, wool and hair are seen.

Treatment / Control: Many dips, sprays, or pour-on products may be effective against lice. Ivermectin injection works well against sucking lice, but not against biting lice. Severe infestations may require re-treatment in 10-21 days to kill lice that hatch from eggs laid before the first treatment.

When treating for lice, it is important to treat all animals in the group at one time. Otherwise the lice will spread from untreated animals back to the treated ones.