Published Jun 1, 2018

PFI members experience poultry deaths caused by gnats

By Meghan Filbert

Over the span of two days, May 22 to 23, 2018, Garrin and Kristten Buttermore of Uncle G’s farm in Ogden, Iowa lost approximately 100 broiler chickens. The USDA promptly responded to this emergency and tested for bird flu since the birds were dying quickly and in large numbers. The bird flu results came back negative.

Upon further inspection, the birds had gnats in their throats and lungs. Garrin Buttermore suspects Buffalo gnats. The broilers received numerous gnat bites that resulted in an anaphylactic reaction. A veterinarian told Garrin the life cycle of gnats is about three weeks ending just about the time mosquitoes appear. This makes late May a critical time to watch for this issue. In other parts of the U.S., the gnats are killing larger livestock and deer.

Buffalo gnats are also known as black flies. Photo courtesy of Darren Blackford, USDA Forest Service,

Garrin shared his experience on the PFI livestock discussion list, and other members weighed in with similar stories. Terry LeDoux of Tipton experienced this years ago and says, “A strong breeze and darkness help hugely.” He recounts the birds pilling on each other as they tried to get away from the gnats. In response to the issue, Terry changed his broiler start date and doesn’t order chicks until the third week of May. By the time the chicks are done brooding, the Buffalo gnats are near the end of their cycle. “This has been a life saver for me,” said Terry.

Jim Jansen of Elkader says he has gnats every year because he’s close to the Turkey River. He’s learned a few lessons on how to protect his birds since he finds they aren’t good at avoiding gnats. Jim says, “The key is to provide indoor shelter. The smaller the opening into shelter the better. They are the worst when it is hot and humid – no wind. So will be forced to put a fan in shelter. You can also keep a fan on them where they feed and water.”

Brian Nowak-Thomson of Mount Vernon has found that using vanillin helps. Vanillin is extracted from vanilla beans or can be made synthetically. He boils about two tablespoons of vanillin crystals in water to dissolve it (noting it isn’t very soluble). He then dilutes the solution in a gallon of water and fills a small pump sprayer. About every two days, Brian sprays the chickens while they roost, and he also sprays the vents on his chicken wagon. Tom McDermott of Clinton gives his chickens access to tubs of diatomaceous earth and says the dust baths seem to help.