ST. PAUL (AP) — Minnesota researchers are examining how wild birds are affected by eating crop seeds treated with insecticide.

Julia Ponder at the University of Minnesota’s Raptor Center has been testing various doses of neonicotinoid insecticide on chickens. She’s found that the animals will fall asleep or have muscle spasms, Minnesota Public Radio reported .

“What we’re doing is very preliminary but it’s going to have significant ramifications,” Ponder said.

Researchers are concerned that wild birds that ingest the insecticide will become more susceptible to predators or disease.

Neonicotinoid insecticide was introduced on the market 20 years ago as a safer alternative to conventional insecticide. The insecticide is typically applied to corn or soybean seeds before planting.

However, treated seeds are often spilled during the planting stage, and many animals eat those seeds.

“Everything from pheasant to blackbirds, house sparrows, deer, raccoons, bunnies, mice, squirrels. Lots of different animals are coming to the spills,” said Charlotte Roy, a research scientist with the Department of Natural Resources.

Researchers estimate that at least 15,000 large seed spills happen in the state during a spring planting season.

Companies that produce the insecticide warn farmers to clean up or cover spilled seeds because they can be toxic to wildlife.

Syngenta is one of the largest sellers of the insecticide. The company said it hopes to educate farmers on the proper usage of treated seeds to minimize their exposure to wildlife.

“Neonicotinoids are an essential crop protection tool for farmers and, when used according to the label, safe for the environment,” the company said in a statement.

Despite the potential for exposure, populations of grouse and prairie chickens in the state are doing well, according to the North American Breeding Bird Survey.