Some people wonder if chronic wasting disease in deer, a similar ailment to mad cow disease, could come from the illegal use of animal by-products in deer feed.

That concern has been raised by the chairman of the Wisconsin Legislature’s Natural Resources Committee.

Chronic wasting disease has been found in southern Wisconsin, and state officials have warned that during next fall’s hunt, tens of thousands of deer carcasses might be dumped in landfills by hunters who refuse to eat them, even though there is no evidence humans can catch the disease from deer.

The United States banned the use of animal by-products in cattle feed in 1996, which probably is why this country hasn’t had an outbreak of mad cow disease like the one that killed dozens of people in Great Britain.

Many doctors think the British disaster in the late 1990s, which resulted in the slaughter of hundreds of thousands of cattle, was caused by abnormal proteins called prions. They were mixed into cattle feed in the form of ground-up bones, brains, lungs, spinal columns, spleens and blood.

Wisconsin Rep. DuWayne Johnsrud, who chairs his state’s Natural Resources Committee, worries that something similar has happened with deer feed in this country.

“Feeding wild deer to produce better antlers really took off a few years ago with the growth of the quality deer management idea,” said Johnsrud, an Eastman, Wis., hog farmer who once worked in livestock feed manufacturing.

“There are all sorts of commercial products on the market. Some are made by big companies, and I don’t think we have to worry much about them. But a lot of feeds are mixed up in barns and garages by what I call the Bubba element, and some of the people who make them have told me that they mix bone meal, blood and organs into the feed to help bucks grow better antlers.”

Johnsrud noted it’s illegal to mix animal by-products in feed for ruminants animals with multiple stomachs such as deer and elk.

“But no one checks these little guys to find out what they’re putting in the feed,” he said, “and it has become a cottage industry in the area where CWD has been found.”

Chronic wasting disease has the potential to wipe out a substantial number of deer. It was first detected in Colorado, and its spread to Wisconsin has raised concerns there and in neighboring states such as Michigan.