Mite and lice infestations can pose a risk to flocks, but they can be easily controlled
A constant problem for small sized free-range chicken flocks is that they are at risk of encountering lice and mites. The solutions are relatively simple, though.
According to Merck’s online Veterinary Manual, lice are transferred from one bird to another when they are in close contact to each other. Large populations of lice can lead to decreased reproductive potential in males and decreased egg production in females.
Lice infestations can be fatal to young chicks, but in most cases lice won’t kill a mature bird. Lice and their eggs are usually spotted under the wing or around the vent.
Mites are nocturnal and hide under manure, on roosts, and in cracks and crevices. They reproduce more quickly in the warmer months.
While all wild birds are carriers of lice and mites and pose a constant risk to flocks, these two parasitic insects are transferred most commonly by equipment and personnel.
Egg crates and egg flats that have been on other farms or in other poultry houses are common culprits. Some lice are transported from host to host by louse flies, as well.
Retired University of Arkansas Poultry Extension Specialist Jerry Wooley said lice and mite infestations are relatively easy to identify and control.
“Watch for birds picking at themselves and a loss of feathers,” Wooley said. “You can spot the lice and mites moving around on the eggs and feathers.”
Birds can be treated with a dry Sevin dust or liquid pesticide application, Wooley said.
“You can use a Sevin dust or spray, but I prefer the spray. Just hold the bird by its feet, and make sure you get a fair amount in the plumage.”
Sevin wettable powder has a greater concentrate than the Sevin dust. Sevin dust contains five percent concentrate, whereas the Sevin wettable powder contains 50 percent, Wooley said.
With free-range flocks, controlling what wild birds come in to contact with free-range chickens is difficult. Wooley said such flocks are at a higher risk for lice and mite infestations spread by wild birds. This makes identification and treatment even more important.
Good sanitation practices can help prevent a buildup of mite populations. It is recommended to use a high-pressure sprayer on hiding spots for mites, including on roosts, behind the nest boxes, and in cracks and crevices. Dust applications are also effective on the ground near the roosts.
Applying diatomaceous earth dust on the ground may also be effective, but Wooley advises apply at a high rate when humidity is high.
“Spreading agricultural lime will help keep the smell down, and that will help keep the flies to a minimum, and it will help raise the ph level just a little bit too. Mites harbor in the wood, so I’d recommend using a residual like Permethrin on the rails, walls and anything wooden on the premises,” Wooley said.
Additionally, Wooley said insecticide treatments won’t kill the eggs, so it is advised to repeat treatment after 10 days to ensure proper control of mites and lice.