AGRICULTURAL EXTENSION SERVICE
External Parasites of Poultry
Prepared by Veterinarians in the Department of Veterinary
Science of the University of Florida Agricultural Experiment
Station and the Florida Livestock Board.
Several species of lice infest chickens and turkeys and more
than one species may be involved at the same time. They have
biting and chewing mouth parts and ordinarily feed on portions
of feathers and scales on the body of the bird. The head louse and
body louse are the two most commonly found on chickens. Ducks
and geese have lice infestations but seldom in sufficient num-
bers to cause appreciable damage.
Lice are easily visible and most common among the feathers
of the back, neck, vent, and breast of the chicken. Heavy infesta-
tiohs may damage the plumage, cause an irritation of the skin
and a failure to gain weight. Lice may cause reduced egg pro-
duction and even kill birds.
All lice spend their entire lives on the birds. Female lice lay
eggs on various parts of the body. The adult stage is reached
in about 3 or 4 weeks after the eggs are laid. Therefore, control
is primarily directed toward destroying the parasites on the
Several insecticides are effective in controlling lice. They
may be applied as dips, dusts, sprays or roost paints. The method
of control can best be determined by the individual according
to facilities and size of the flock.
An effective dip can be prepared by adding 1 ounce of sodium
fluoride powder to each gallon of warm water. Each bird should
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
Florida State University and United States Department of Agriculture, Cooperating
M. O. Watkins. Director
be held by the wings and kept in the dip for 20 to 30 seconds
The head should be ducked once or twice. Use dips on warm
days only and early in the day so the birds will dry by night.
One small pinch of sodium fluoride or sodium fluosilicate pow-
der may be applied to the head, neck, tail, breast, vent and each
of the thighs and wings. Sodium fluoride should be diluted with
3 parts talc or flour if it is dusted with a shaker can. A 5%
or 10% DDT dust, derris powder containing 1% rotenone, or
powdered sulfur can be applied to the skin with a shaker can.
Powdered sulfur must be applied liberally to be effective. In Flor-
ida 4% malathion dust has been rather extensively and success-
fully used on chickens.
Lindane as a 1% spray may be used in a power sprayer or a
garden type sprayer on the inside of a poultry house. The birds
should not be allowed in the house while lindane is being applied.
Malathion as a 0.5% spray has been applied directly to chickens
with good results.
The following insecticides have proven satisfactory for con-
trol of lice as a roost paint: undiluted 40% nicotine sulfate, or
1% lindane, or 1% malathion. One pint of either of these paints
will cover about 150 to 200 feet of roost. Vapors from roost
paints kill lice on the roosting birds. Roost paints should be
applied about half an hour before roosting time.
Mites are minute parasites visible with difficulty and may be
found on any part of the body depending upon the species pres-
ent. They burrow into the tissues and are bloodsucking para-
Two groups of mites infest poultry. One group feeds on
birds at night and hides in cracks and crevices during the day.
When the premises are heavily infested the mites may be ob-
served during the day. Another group spends its entire life
cycle on the bird. Mites may be spread from farm to farm by
poultry, birds, crates, coops and persons in contact with infested
birds or infested premises. Heavy infestations may develop
in a short time, especially in summer.
Most mites found on chickens can live on turkeys but they
do not appear to trouble turkeys to the extent they do chickens.
Severe infestations of mites create more damage than lice. When
mites penetrate the tissues they cause an intense irritation and
scab formations. Loss of blood results in anemia. Birds may
become weak and thin. Egg production may decrease consider-
ably. Young and laying birds may die.
Each kind of mite requires separate consideration for con-
trolling infestations. Insecticides may be used as dusts, sprays,
dips, roost paints and ointments.
Chicken Mite.-These mites attack poultry at night and hide
in cracks of the house during the daytime unless a heavy infesta-
tion occurs. Masses of the mites, eggs and silvery skins shed
by the immature mites may be found in cracks of the poultry
houses and coops. In summer, eggs may hatch and mites ma-
ture in 10 to 14 days.
Best results can be obtained by spraying all the inside sur-
faces of the building with 1% malathion, 0.5% lindane or a 2.5%
DDT. Hiding places such as cracks and crevices, between boards,
etc. should receive special attention. A repeat application may
be necessary in 10 to 14 days.
Northern Fowl Mite.-These mites remain on the birds most
of the time. They congregate near the tail, vent and neck.
A dip prepared by adding 2 ounces of finely ground sulfur
and 1 ounce of soap to each gallon of warm water may be used.
Birds should be dipped on warm days only. Powdered sulfur
dust may be applied liberally. Malathion as a 0.5% spray has
been applied directly to chickens and litter with good results.
Undiluted 40% nicotine sulfate may be applied to the roosts
about half an hour before roosting time. Two or three applica-
tions of roost paint at 1 to 2 week intervals may be necessary.
Scaly Leg Mite.-These mites attack the feet and lower legs
of poultry and cause the condition called "scaly leg". There is
an irritation and a roughening of the surface of the legs, with
scab and crust formations that push the scales upward. Birds
may lose flesh, become lame or lose an end joint or toe.
Crude oil applied to the feet as a dip or with a brush is usually
effective. A second application may be indicated about a month
later. Kerosene is less effective than crude oil. Another method
is to soak the feet and legs in warm soapy water until all scales
are loosened. Then apply lard containing 15% sulfur to all
Depluming Mite.-Infestations by depluming mites are ob-
served mostly during summer. They tend to disappear during
the winter months. The mites burrow into the skin at the base
of the feathers. The irritation produced may cause birds to pull
The sulfur dip as recommended for Northern mites may be
used. Repeat treatments may be necessary in 3 or 4 weeks.
Tropical Feather Mite.-These mites are usually most numer-
ous among the fluff around the vent. They have been observed
more commonly in cage plants. First evidence usually occurs
when the mites are found on the eggs. Spraying the cages and
birds with 1% malathion or 0.5% lindane gives effective con-
trol. The cage supports should be sprayed with crude oil.
Dusting affected birds with sulfur also is effective.
Fowl ticks, chicken ticks or "blue bugs" are bloodsucking
parasites. They attack chickens, turkeys and other birds. In-
fested birds may become weak, lose their appetite and lose weight
and their comb and wattles become pale. Heavy infestations
may kill birds.
Fowl ticks are not easily detected for they hide and breed
in cracks and crevices or under boards of the poultry house and
coops. The- ceiling may become as heavily infested as other
parts of the house. They have the ability to live for long periods
Toxaphene, chlordane or lindane used as a 0.5% spray, a 5%
DDT solution or a 1% malathion solution will control fowl ticks.
All surfaces of the poultry house should be thoroughly sprayed,
paying particular attention to likely hiding places. Repeated
treatments at 10 day intervals are necessary. Cresote oil,
anthracene oil and crude oil are less effective.
Sticktight fleas are a common external parasite of poultry.
They are usually found in clusters on the comb and wattles and
around the eyes.
The poultry houses, litter, and infested portions of yards
should be sprayed with 1% malathion, 0.5% lindane or 2.5%
DDT. Repeat applications may be necessary.
Most insecticides are poisonous for man, animals and birds
and should be handled with care. Masks should be worn to pre-
vent inhalation of insecticides. Any materials spilled on the
skin of the operator should be removed by thorough washing.
Do not contaminate feed and water with an insecticide.
Dilution Chart for Mixing Sprays
(Courtesy James E. Brogdon, Entomologist, Florida
Agricultural Extension Service.)
Amount of Insecticide Concentrate to Add to Water for Desired Spray
Percent of 10.5% 1 1% 2.5%
Insecticide 1 gal. 5 gal. 1 gal. 5 gal. 1 gal. 5 gal.
25% ................... 2% oz. 13 oz. 5 oz. 1 lb. 11 oz. 13 oz. 4 lbs. 3 oz.
50% ................. 11/3 oz. 6 oz. 2% oz. 13 oz. 6 oz. 2 Ibs. 1 oz.
20% ............. 6% TBS 1 pt. 13 TBS 2 pt. 1 pt. 2% qts.
25% ................. 5 TBS 1% cup 10 TBS 3 cups 1% cups 2 qts.
50% .................. 2% TBS % cup 5 TBS 1% cups % cup 1 qt.
gal. = gallon
pt. = pint
oz. = ounce
qt. = quart
3 teaspoons = 1 tablespoon
2 tablespoons = 1 fluid ounce
8 fluid ounces = 1 cup
TBS = tablespoon
Ib. = pound
2 cups =1 pint
2 pints = 1 quart
4 quarts = 1 gallon
Benzene hexachloride dusts or liquids have an undesirable
musty odor and may produce off-flavors in eggs and meat. They
should never be used about the poultry house.
Malathion dust (4%) also has been reported responsible for
undesirable flavor to eggs.
Insecticides should not be used at strengths more concen-
trated than those recommended on the container labels.
When DDT is used about poultry premises, at least 30 days
should elapse before birds are marketed.