Lice are external parasites that feed on chickens’ skin and feathers. They are very small but visible, as they move between the feathers. Their whitish egg masses are located at the base of feather shafts.
Lice-infested chickens act nervously, scratching and pecking themselves frequently. Their feathers look dry and ruffled. The constant irritation caused by lice leads to weight loss and decreased egg production. Severe infestation can be fatal for young chickens.
Can it spread?
Lice can spread from chicken to chicken. In fact, wild birds and new introductions to a flock are the most common sources of lice infestations.
The best way to prevent lice from becoming a serious problem is by examining your chickens frequently. Look between their feathers every two weeks. Also, be sure to quarantine and check new birds for lice before introducing them to your flock.
If lice have already infested your flock, insecticides are the most reliable method to get rid of this pesky problem. Lice are sensitive to most insecticides, but be certain to use a product approved for use with poultry; avoid contaminating eggs, feed and water. Two treatments of dipping, dusting or spraying seven to 10 days apart will break the infestation cycle.
About the Authors: Dr. Jose A. Linares, DVM, ACPV, is the Resident Director of the Texas Veterinary Medical Diagnostic Laboratory, Poultry Diagnostic Laboratory in Gonzales, TX. Dr. John El-Attrache, PhD, is an Assistant Professor in the Department of Veterinary Pathobiology in the College of Veterinary Medicine at Texas A&M University.