Skin diseases, lice and mites, are brought to a flock by wild birds, rodents, and new chickens. They may be carried on used feeders, waterers, nests and other equipment. Take preventative measures by regularly cleaning the brooding area, hen house and outside pen. If you recycle used equipment, scrub and disinfect it before putting it to use. Periodically check your chickens for signs of disease and infestations.
Lice are a wingless insect that lay their eggs near the base of the chicken’s feathers. Two species of lice affect chickens: body lice and quill lice. Quill lice tend to lay their eggs in a specific location, and body lice will lay their eggs on the entire body surface of the chicken. They feed on dry skin cells; they do not suck the blood of the chicken. However, they will feed on the blood that develops when the chicken scratches and bites at the lice. Symptoms of lice include itchy, irritated skin, biting or rubbing and pulling out of feathers. According to the Ohio State University Extension office, lice are treated with insecticidal powders such as carbaryl. Completely dust the bird with the carbaryl powder carefully so you do not breathe in the medication. Re-treat the bird every two weeks to kill the eggs, which will not hatch during the previous treatment. These parasites spread rapidly, so if untreated, they will infect the entire flock.
Two major species of mites affect chickens: the Leg mite and the Chicken mite. Chicken mites are tiny red or light brown insects that look like spiders crawling on the skin and sucking the chicken’s blood at night. During the day, they inhabit perches and nests. Mites, unlike lice, can survive without a host for a short time. Signs of infestation include darkened feathers, scabbing, and mite eggs on the fluff feathers. Leg mites get under the scales on a chicken’s shanks, causing them to be raised instead of lying smoothly. A serious infestation is painful and causes the chicken to walk stiff-legged. Oral Ivermectin is a very effective treatment for infected birds.
Avian Pox is a virus transmitted directly from infected chickens or mosquitoes, which have had contact with an infected bird. Symptoms often include small yellow warts on the face, comb, and wattles. They increase in size and develop dark brown scabs at which time the wart falls off. Dr. Gary Butcher, DVM, for the University of Florida, states that this disease is slow spreading. Vaccinating chickens at 12 to 16 weeks of age can prevent the disease.