The poultry
louse is wingless, skin colored, and has six legs. There are several species
that may be found on chickens, turkeys, ducks, and other fowl. When eggs
are laid, they attach to the host's feathers. The generation time is from
two to seven weeks depending on the species. The entire life cycle of
the louse is spent on the host unless by chance the insect is disturbed
and happens to be found on a human or other animal. Lice generally feed
on skin particles and feathers, but do not have sucking mouthparts and
do not feed on blood. When examining a bird for lice they are usually
found on the skin around the vent and under the wings.
Mites
There
are several species of mites that may be found on poultry. This insect
can be spread from farm to farm by infested crates, chickens, or other
birds.
Common
mites
Common
or Red mite is a specie that does not remain on the host at all times.
During the day, this mite finds refuge in cracks and crevices of nests,
roosts, and other places in the poultry house. At night the mites leave
their hiding places, find a bird to provide a blood meal, and then head
back into hiding. This parasite may go undetected unless the birds are
examined during the night. If a flock seems lethargic, the birds are droopy
and weak, or they have pale combs and wattles, mites may be the problem.
The birds themselves do not need treatment. Instead a thorough cleaning
and insecticide treatment of the house are recommended.
Northern
Fowl Mite
The Northern Fowl Mite is quite different in that it lives on the birds
at all times. This specie of mite is usually found on the feathers around
the vent. Large infestations on a bird can make the feathers appear almost
black because of the eggs and excrement. Mites can easily be spread from
bird to bird and the numbers of insects on a single bird can increase
rapidly. Growth rate and egg production can be reduced because of mite
infestations. As the number of mites increases the birds can appear pale,
droopy, become anemic, and the mortality rate can increase. The Northern
Fowl Mite is usually a cool weather pest, but can cause problems year-round.
The mites can live from several days to 3 weeks detached from the host.
Because of this, depopulating a house to get rid of the mite problem should
include a down time of at least a month.
Depluming
Mite
Another specie of mites that can cause problems is the Depluming or Feather
Mite. Contrary to some reports this mite does not chew on the feather
and make them fall out. Instead, the mite burrows into the skin at the
base of the feather and irritates it, so the bird pulls the feather out
in an attempt to eliminate the irritation.
Scaly
Leg Mite
This specie lives under the scales on the legs and feet of birds. Because
it lives under the scales, the mite causes itching and irritation, also
causing the scales to appear pushed up or thicker. Sometimes a crusty
appearance can be seen on the feet and legs. Older birds seem to be more
likely candidates for this insect. Many years ago, producers treated birds
with these characteristics by standing them in a container of kerosene
for a few minutes. The kerosene seemed to do two things. First, it had
enough oil in it to seal off the air and the insects would not survive
and secondly, the oil also helped soften the crusty scales, so they could
be eliminated and replaced. An alternative to kerosene is baby oil or
something similar that acts in the same manner. The legs and feet can
also be treated with an approved insecticide, and then rubbed with oil.
Chiggers
The chiggers that cause problems with poultry are the same ones that cause
similar problems with people. It is a specie of mite that is non-specific
to a host. The irritations, whelps, and inflammations are the result of
the insect attaching itself to the skin. If birds have multiple lesions
they may become irritable, droopy, and will not eat. If birds are to be
slaughtered the lesions will result in downgrades or condemnations. Chiggers
are normally found on grass and weeds and may be a problem if birds are
allowed to range in areas with tall vegetation. Chigger problems can be
reduced if the vegetation is sprayed with an approved insecticide. Malathion
dust or spray is an example. With any insecticide the label directions
on mixing, application, and restrictions should always be followed.
Control
of Lice and Mites
The old
saying "an ounce of prevention is worth a pound of cure" applies
here. If keeping an infestation from getting started can prevent insect
problems, it is by far better than attempting a control. Eliminating wild
birds from the poultry house is a good place to start. This can be done
by repairing any holes in the roof or sides of the house that birds might
use as entry points. Preventing feed spills and not feeding chickens outside
the poultry house will also discourage wild birds from remaining in the
area. If wild birds start to build nests in or around the poultry house,
the nesting materials should be removed immediately. Artificial snakes
and owls can be placed in or around the poultry house as an additional
means of discouraging wild birds. Another important preventive measure
is to be sure all equipment and new birds coming into a flock are free
of lice and mites. Some small poultry producers provide a container of
sand where the birds can dust themselves. In addition to the sand, a powdered
insecticide such as Sevin can be mixed in the container, and while the
birds dust themselves they are applying the insecticide to keep down infestations.
Treating
for Lice and Mites
Lice
are not usually an issue in commercial flocks, but may show up in small
flock situations. Mites on the other hand may be a problem in all sizes
of production. As mentioned previously, a good isolation and sanitation
program can help prevent problems with external parasites. If external
parasites are detected in the flock there are several chemical treatment
options available.
Chemical
controls for treating houses, nests, roosts, etc include malathion,
carbaryl (Sevin), coumaphos (Co-Ral), and Rabon. If common mites
are suspected, careful treatment of cracks and crevices is a must
and a repeat treatment may be necessary. If direct treatment of
the birds is necessary, such materials as malathion, carbaryl, Rabon
(all three are available in either the dust or spray form), coumaphos,
and permethrin (trade names include Atroban, Eciban, Purina Hard
Hitter, Insectrin, Overtime, Permectrin) can be used. For all chemicals
used for poultry, the label directions for mixing, application,
and precautions should always be carefully followed.