Backyard chicken aficionados take note: A preponderance of pests may be afflicting your dutifully tended flock without your knowing. According to new research published in the Journal of Medical Entomology, the diversity of parasites among backyard chicken coops "greatly exceeds" that of commercial chicken operations, an issue the researchers say some homeowners aren't aware of.
Scientists from the University of California–Riverside examined 100 adult hens throughout 20 Southern California backyards, studying the birds for ectoparasites—parasites like fleas or lice that live around the skin, but not inside of the body. In addition to scouring the cracks and crevices of nest boxes, coops, and perches for traces of any parasitic evidence, the researchers studied the chickens' skin, fluffy vent feathers, wing feathers, combs, wattles, and eyes.
Just four locations throughout the course of the study were parasite-free.
About 80 percent of the examined flocks were afflicted with ectoparasites, the researchers found—lice, mostly, as many as six different species—and about a third were infested with at least two species of ectoparasites. Several chickens were found with hundreds of lice on them alone. Overall, just four locations throughout the course of the study were parasite-free.
It's not surprising that backyard coops are more prone to parasites than factory farm operations. Homegrown and commercial flocks alike share a prevalence for several of the same ectoparasite species examined throughout the course of the study—it's just that the arguably inhumane conditions of a factory farm end up minimizing natural parasites for mass-production's sake.
Battery cages, for example—small wire cages used commonly by Big Poultry to house multiple laying hens at once—are so cramped and unsanitary that hens are often unable to ever fully extend their wings, causing them to suffer from deteriorating skeletal systems. Battery cages also elevate chickens off the ground, however, where developing parasites live, and provide fewer nooks and crannies where pests can survive.
Worth studying further, the paper's authors note, is that battery cage operations are falling by the wayside—thanks in part to legislation like California's Proposition 2, which requires that egg-laying hens have enough room to stand, stretch, and turn around, and a companion law requiring that any eggs sold from out-of-state comply with the same guidelines. According to the cooperative United Egg Producers, organic and cage-free egg production accounted for 8.7 percent of the country's egg flock last year. Commercial cage-free, free-range, and pastured chicken egg operations are likely to continue becoming more commonplace—and with them, perhaps increased economic risks that could accompany a parasitic infestation. "These more open habitats will likely increase the risk of ectoparasite acquisition and transmission," the researchers write.
On a smaller scale, managing chickens for pests like lice is a manageable task. So in the meantime, there's no need for backyard keepers to board up their coops and get their roasting pans ready just yet.
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