The northern fowl mite, or feather mite, Ornithonyssus sylviarum (Canestrini and Fanzago), is a very important external parasite of poultry with heavy populations capable of reducing egg production up to 10 percent to 15 percent. Mites can also annoy egg handlers and other persons. Mites are often first noticed on the eggs. Check for mites first on the vent, then tail, back and legs of layers. Feathers become soiled from mite eggs, cast skins, dried blood from feeding and excrement.
The entire life cycle is completed on the bird and consists of the egg, larva, nymphal stages and adult. The eight legged adult is about 1/26 inch long and dark red to black in color. The entire life cycle can be completed under ideal conditions within a week.
With early detection, only a part of the caged-layer house may need to be treated. Monitor weekly at least 10 randomly selected birds from each cage row in the entire house. Mite populations will increase in cooler weather.
The chicken body louse, Menacanthus stramineus (Nitzsch), can decrease egg production in caged layer hens. The skin of infested birds becomes irritated and red with formation of localized scabs and blood clots. In addition to feeding on skin fragments, feathers and debris, lice can attack young quill feathers feeding on blood. Although found naturally infected with the virus of eastern encephalomyelitis, it is not considered an important vector. Adult chicken lice are flat-bodied, yellowish colored, 1/16 inch long with chewing mouthparts.
The chicken mite, Dermanyssus gallinae (DeGeer), sucks blood from poultry at night and remains secluded during the day and in cracks and crevices. When numerous, weight gains and egg production can be reduced. These red and gray mites barely can be seen without a magnifying glass. The life cycle may be completed in seven to ten days during warm weather with inactivity during cold weather.
The common bed bug, Cimex lectularius L., occasionally attacks poultry. It hides in cracks within the housing during the day and feeds mostly at night on blood while the host is asleep, causing small, hard, swollen, white welts which become inflamed and itch severely. It is rarely seen on poultry during daylight hours. An infestation can sometimes be recognized by blood stains and dark spots of excreta. The adult is reddish-brown, oval-shaped, flattened and about 1/4 inch to 5/8 inch long. There may be three or more generations per year. No evidence indicates a disease is spread.
Occasionally the flea is found in the poultry house. It is usually first noticed in the litter where a wide range of hosts are attacked including rats, mice, chickens, humans, etc. Bites annoying egg handlers occur primarily on the ankles and legs causing a raised (swollen) itching spot. The adult flea is an excellent jumper passing through a complete life cycle consisting of egg, larva, pupa and adult. The life cycle varies from two weeks to eight months depending on temperature, humidity, food and species. The most common flea found in Ohio is the cat flea, Ctenocephalides felis (Bouche). The adult is 1/16 to 1/8 inch long, dark reddish-brown, wingless, hard-bodied, has three pairs of legs and is flattened vertically (bluegill fishlike).
The darkling beetle or lesser mealworm, Alphitobius diaperinus (Panzer), is rapidly becoming more of a nuisance in the poultry operation. Large populations of beetles sometimes migrate into nearby residence areas, especially during litter clean-out time. Although beetles can fly up to one mile, most crawl at night from litter disposed to neighboring fields and homes.
Beetles are frequently associated with poultry feed, preferring grain and cereal products that are damp, moldy and slightly out of condition. Both adults and larvae consume poultry feed in amounts costly to the producer. Larvae are known as lesser mealworms.
Increased importance has been placed on control of this beetle. Both adult beetles and larvae act as reservoirs for many poultry pathogens and parasites. Scientists have been able to transmit the causative agent of acute leukosis (Marek's disease) in chickens with this beetle. Positive confirmation of the transmission has been made under both laboratory and field research conditions.
Marek's disease usually affects birds between three and four months old. Symptoms are characterized by various degrees of paralysis, most easily observed in legs and wings. Droopy wings, gasping, loss of weight, pallor and sometimes diarrhea are also symptoms. Birds severely affected may be found lying on their sides with one leg stretched forward and the other held behind. The disease affects both broiler and egg laying types of poultry. Losses can reach two percent of the flock per day, and mortality may exceed 30 percent of the flock within a few weeks.
Acute leukosis is highly contagious and has been shown to be airborne. Contamination may persist in the environment because the darkling beetle may serve as a reservoir for residual contamination. Beetles have been observed feeding on carcasses of poultry dead of leukosis, and it appears that beetles may become contaminated in the process. Adult beetles are capable of retaining the contamination and transmitting the leukosis when eaten by chickens, in the opinion of some scientists. Other diseases which are spread include the causative agents of avian influenza, salmonella, fowl pox, coccidiosis, botulism and new castle disease. They also act as vectors of cecal worms and avian tapeworms.
In the poultry house, the beetle can lay up to 800 eggs in litter during a 42-day period. Eggs develop into larvae in four to seven days. The life cycle requires about 42 to 97 days depending on temperature. Beetles live up to three months to a year. Adults are black or very dark, reddish- brown and about 1/4 inch long. Larvae are yellowish-brown (wireworm-like) up to 3/4 inch long and accumulate in dark corners of manure or litter, especially under sacks, in bins or in places where feed is stored. Pupation occurs in the litter, soil and side walls of poultry houses. They migrate frequently throughout the litter generally coming in soil contact.
Adult chickens and chicks are more likely to eat the beetles and their larvae than poults or turkeys. Consumption of beetles and larvae, rather than providing "extra protein" in the diet, actually has a negative effect on feed conversion and rate of gain according to research.
Mature larvae of the hide beetle, Dermestes maculatus (DeGeer), have the habit of boring into various hard surfaces to pupate, usually preferring softwoods. Some may climb 24 to 36 feet and bore into wood posts, studs and rafters, seriously weakening and "honeycombing" these structures. Larvae are especially troublesome in poultry houses, damaging yellow pine, foam insulation, styrofoam air baffle boards, paneling, drywall and even PCP (Penta Ready) chemically treated wood in some cases. Larvae emerge from the litter, climb the walls and bore into soft building material, often escaping cannibalism during the pupation period. Hide beetles are larger than darkling beetles, about 1/3 inch long, dark brown on top, with a mostly white undersurface (belly). Each female lays about 135 eggs, which hatch in 12 or more days. The life cycle requires 40 to 50 days. Larvae are thickly covered with long, brown hairs, grow to about 1/2 inch long and have two spines on top near the tail end, which curve forward. Reasonable control has been achieved by applying tetrachlorvinphos (Rabon) 50% WP in the dry form to the building walls. Make treatments with an electrostatic duster so as to negatively charge the particles, providing better adhesion to the wall surface. A distributor for the duster (model DM-9) is Echo Inc., 3150 MacArthur Blvd., Northbrook, Illinois 60062. Hide beetles can be killed with a 1.35% pyrethrin residual emulsion concentrate.