For chickens, a dip in the sandbox is good hygiene.
Cage-free flocks that “bathe” by flapping around in diatomaceous earth (a fine dust of fossilized algae) and sand prevent serious mite infections, researchers report September 14 in the Journal of Economic Entomology. Major infections of more than 100 mites per bird make hens lay 2 to 4 percent fewer eggs on average. So access to boxes filled with dust, which look like tiny sandboxes, makes sense for birds’ health and for farmers’ wallets.
Dust baths damage mites’ waxy outer coating and kill the pests by drying them out. Scientists already knew dust can help manage mites in badly infested birds but weren’t sure if it could also be preventative.
Researchers from the University of California, Riverside kept cage-free chickens in poultry houses with dust boxes. The scientists infected clean chickens with 20 to 30 mites each, for two consecutive weeks, and then monitored the size of each bird’s infestation. Over six to 10 weeks, each dust-bathing hen carried 100 or fewer mites, on average. When the dust baths were removed, mite populations skyrocketed. The new results point to dust boxes as an alternative to pesticides for cage-free and organic farms, the researchers say.