Mites on Poallry 493 Lindane probably is the most effec- should be applied liberally, to the tive. Lindane may be applied to the point of runoff, on roosts and perches roosts with a small paintbrush or and, if desired, lightly to nesting boxes sprayed over the roosting surfaces, and floor. A small knapsack sprayer is nesting boxes, and floor. To prepare suitable for all but large establish- a paint containing about i percent of ments. Five gallons of spray are enough lindane, you mix 5 ounces of lindane to treat buildings housing 750 to 1,000 wcttablc powder containing 25-per- chickens. cent gamma isomer (or 6 ounces of 20-percent lindane emulsifiable con- IRWIN H. ROBERTS is a parasitologist centrate) with a gallon of water. You in the Animal Disease and Parasite Re- apply the paint to the roosts with a search Branch. He was graduated from small paintbrush to the point of runoff. Alfred University and has the degree of Spraying poultry houses is a little doctor of veterinary medicine from Cornell more effective than painting in that University. He entered the former zoological coverage of roosting surfaces is usually Division of the Department of Agriculture better. If many birds are involved, in ig^7^ and siyice 1^40 has been engaged spraying is easier and takes less time. in investigations of parasitic diseases. To prepare a spray containing about G. L. SMITH is an entomologist in the 0.5 percent of lindane, you add three- Entomology Research Branch. He is a fourths pound of 25-percent lindane graduate of Mississippi State College and wettablc powder (or i pint of 20-per- Louisiana State University. Since ig^S cent lindane emulsifiable concen- he has been project leader for research on trate) to each 5 gallons of water. the control of lice, mites, and fleas affecting Malathion also is effective against livestock. Î71 jgji he became assistant sta- lice when used at a i-percent concen- tion leader of the Department s laboratory tration as a roost treatment. Sprays at Kerrville, Tex.

Mites on Poultry

ÏRWIN H.ROBERTS AND C.U SMITH

MITES on fowl arc sometimes mis- forages upon the roosting birds to suck taken for lice. Actually they are quite their blood. The second group spends different. the entire life cycle on the birds; they Parasitic mites are so small that they burrow into the skin, into the shafts are barely visible to the naked eye. All of the feathers, beneath the scales of mites have four pairs of legs in their the legs, and into the internal organs. adult stage. Lice have three pairs of Of the several kinds of mites that legs. Some of the mites are blood- may infest poultry anywhere in the suckers. They may live for a long time United States, the commonest and without food. They and lice are con- perhaps the most injurious is the trolled by different methods. chicken mite {Dermanyssus gallinae). It Two groups of mites attack poultry. is also known as the red chicken mite One spends the greater part of its life or the roost mite. The adult is not more cycle in crevices about the poultry than one thirty-second inch long when houses, from which it makes nightly fully engorged with blood—about the 494 Yearbook of Agriculture 1956 size of the head of a pin. Chicken mites is generally found on older birds in the are gray when unfed and reddish after flock. It is less prevalent than the having had a blood meal. When many chicken mite and the northern fowl of them infest a poultry house, they mite. can be found by lifting a clod of Scaly-leg mites usually are first no- manure off the roosts. Joints in the ticed between the toes. As they multi- roosts are often surrounded by tiny, ply they work their way up the leg. salt-and-pepper specks, which are the They cause the scales to separate from excrement of the hidden mites. the skin and the feet and legs to swell After taking a blood meal from the and become deformed. Occasionally bird, the female chicken mite finds a they may spread to the comb and crevice, usually on the roost, and wattles. Scaly-leg mites are too small deposits a few eggs. She then returns to be seen with the naked eye, but the to the bird for additional meals. She symptoms they produce are detected may deposit 35 eggs in her lifetime. easily. Larvae, which hatch from the eggs in The practice of culling old birds has I or 2 days, do not feed but shed their eliminated the scaly-leg mite to a large skins and then become nymphs. The degree, and it is now rarely seen except nymphs attack the birds, suck blood, in small farm flocks. molt, suck blood a second time, molt Closely related to the scaly-leg mite again, and become adults. In warm is the depluming (or body-mange) weather or in heated buildings, the mite of chickens and other birds (Kne- entire cycle may take only i week. midokoptes laevis var. gallinae). It also Enormous infestations may build up passes its entire life on the bird. It bur- in poultry houses in 3 or 4 weeks. rows into the skin at the base of the The northern fowl mite {Bdellonyssus feathers. It is found only on the feath- sylviarum)^ also called the feather mite, ered areas of the body, usually over the is distributed widely over the United back and sides. The mites cause intense States, but is encountered less fre- irritation, so that the fowl may pluck quently than the chicken mite. It looks out or break ofl* their feathers. You can like the chicken mite but has a differ- see this tiny mite only with a lens or ent life history. microscope. Northern fowl mites normally spend Most of the mites parasitic on chick- their entire lives on chickens or other ens also can live on turkeys and other birds, but they are sometimes found fowl, but they do not trouble turkeys in birds' nests and can breed on or off quite so much as they do chickens. Ap- the birds. Their entire life cycle lasts parently the management practices 8 to 12 days. They can be found on the used for turkeys are not conducive to birds during the day. They move the propagation of mites. The most rapidly. If infested birds are picked up, common mite affecting turkeys is the the mites crawl over the handler's arms chicken mite. The northern fowl mite and sometimes on his clothing. They occasionally is troublesome. Both may usually congregate about the bird's be controlled with the same measures vent and give the feathers a soiled used against mites on chickens. appearance. Their voracious blood- Severe infestations of mites do more sucking habits may irritate the skin damage than lice do. Mites that bur- severely. Heavy infestations may de- row into the skin produce intense skin velop in a short time. irritation and heavy formation of Another mite that lives continuously scabs. Such injury retards the birds and on chickens and other birds is the spoils their appearance when dressed. scaly-leg mite {Knemidokopies muians). Some species cause the loss of feathers, It attacks the unfeathcred parts of the thereby interfering with the regulation legs, burrows into the skin, and causes of body heat. The nests of laying hens a condition like mange of livestock. It sometimes have so many chicken mites Mites on Poultry 495 that the birds cannot remain in them. cation is thorough. Dipping the birds Anemia, caused by the loss of blood, in sulfur baths is laborious, but the re- is common. Heavily parasitized fowl sults are gratifying. Dips may be pre- become thin, weak, and restless. Egg pared by mixing 2 ounces of finely production falls. Young and laying ground sulfur (325 m.esh) and i ounce birds may die. The injury due to mites of powdered soap or detergent to a that live in the internal organs has not gallon of lukewarm water. The feath- been calculated, but may be sizable. ers should be wet to the skin, and the An indirect loss due to bloodsucking head ducked. It is always advisable to mites results from their ability to trans- dip fowl on warm, sunny days or in mit disease, such as fowl cholera and heated buildings. Treatment with Newcastle disease, among flocks. either sulfur dusts or dips should be re- For each of the four kinds of mites peated as required. commonly found on chickens, a differ- An effective and quick treatment to ent method of attack is required. It is eliminate northern fowl mites consists therefore essential to determine what of applying to the roosts or litter a species is present. If two or more species chemical, the vapors of which will de- are present simultaneously, separate stroy the mites on the birds. Undiluted treatments will be necessary. nicotine sulfate (40 percent) may be applied with a brush to the roosts, To CONTROL infestations of the chick- perches, and other roosting surfaces, en mite, an insecticide should be ap- at the rate of i to 1.5 ounces for each plied to the poultry house. It is not 30 feet of roost. As nicotine sulfate vol- necessary to treat the birds. atilizes rapidly, it should be used The first step is to clean the building, shortly before roosting time. About nesting boxes, floor, and dropping pits three applications a week apart are thoroughly; burn the litter; and dis- required to end infestations. The pose of manure. Dried manure should buildings should be ventilated after be scraped from roosts and perches. nicotine sulfate is used. This cleaning should, be followed by Another easy and less hazardous a liberal application of 0.5-percent way is to treat the litter with mala- lindane or 2.5-percent DDT spray to thion. A 4-percent malathion dust ap- the entire interior. Lindane or mala- plied to the litter only, i pound to 50 thion applied to the roosts as a i- square feet of floor space, will control percent paint is also satisfactory against the northern fowl mite. The dust the chicken mite. Lindane and mala- should be applied uniformly with a thion have a further advantage in that plunger or rotary hand duster or a if the birds are returned to the build- shaker can or jar. ings at the close of the day, all their An old, simple, and effective treat- lice will be destroyed. ment for the scaly-leg mite consists in With any of these insecticides, a dipping the feet and legs of infested second application may be required birds in crude petroleum. Usually one in 10 to 14 days, particularly in heavy treatment is enough, but a second infestations. It is not easy to eradicate treatment about a month later may chicken mites entirely. be required in heavy infestations. Because the northern fowl mite re- A mixture of i part of kerosene to 2 mains on the birds most of the time, parts of raw linseed oil also may be insecticidal dusts and dips applied used as a dip for the feet and legs. directly to the birds are effective con- Repeated treatments every 2 to 4 trol measures. weeks, until healing takes place, may Sulfur has been used for many years. be required with this mixture. The treatment of individual birds with For controlling the depluming mite, powdered sulfur is satisfactory if liberal old, established remedies continue to amounts of dust are used and if appii- be efifective. The birds may be dipped 496 Yearbook of Agriculture 1956 in a bath containing 2 ounces of wet- IRWIN H. ROBERTS, a parasitologist in table sulfur per gallon of water. If spot the Department of Agriculture, has studied treatment on a few birds is all that parasitic diseases of livestock in South- seems necessary, a sulfur ointment can western, Western, and North Central be rubbed into the affected areas of States, He is stationed in Springfield, III. the skin. The ointment can be pre- G. L, SMITH in zpjj became project pared by mixing i tablespoonful of leader at the Department's laboratory in flowers of sulfur in one-half cup of Orlando, Fla., in charge of methods and lard or vaseline. procedures for eradicating the screwworm.

Diseases of Ducks

E. DOUGHERTY III

DUCKS arc waterfowl and scavengers PARATYPHOID, or keel, is an infec- by nature and are relatively resistant tious disease of young ducklings (also to many common diseases of birds. of turkeys and other birds). It is caused The large, modern, commercial duck chiefly by a bacterium. Salmonella iyphi- ranch is a long step from nature, how^- murium, and to a less extent by other ever. Confinement creates such prob- species of salmonellas. Mortality is lems as a damp, ammonia-laden at- usually low (less than lo percent) on mosphere; rapid spread of some dis- Long Island, but poor incubator and eases that are almost unknown in wild brooder management increase the ducks (paratyphoid, scrositis, and fowl death rate. cholera); heavy insect populations; The name "keel," which stems from and leg weakness. early observations that the ducks sud- On the other side of the ledger, con- denly keel over when dying, is mis- finement rearing (with a controlled leading. Often the ducklings become water supply) has all but eliminated dehydrated and emaciated and die western duck sickness (botulism), para- slowly. They may gasp for air or sitism, and attack from predatory ani- tremble, as though chilled. mals, which are scourges of wild ducks. The common lesions are small, w^hite The duck rancher has to provide an spots on the liver, cheesy plugs in the escape for moisture to prevent ammo- blind gut, and a thickening of the wall nia burn. To accomplish that he re- of the large gut. places the litter daily or provides wire The best preventive measure we floors over washable pits on at least know of is to fumigate the eggs during part of the building. Other problems, early incubation and the hatching unit such as botulism, have been solved by betw^cen hatches. Potassium permanga- the use of pelleted feed and a constant nate and formalin are recommended. water level. Potassium permanganate crystals Flies can be controlled by modern should be used at the rate of one-half chemicals. They must be checked be- ounce (weighed) and i ounce of for- fore use, however, because some of the malin (measured) to every 8o cubic thiophosphates, w^hich are safe to use feet of incuJDator or hatcher space. in chicken houses, are highly toxic to The potassium permanganate crystals ducks. are placed in an earthenware vessel