The State Game and Fish Department has all but wrapped up collecting samples for its annual chronic wasting disease surveillance program.

Dan Grove, wildlife veterinarian for the North Dakota Game and Fish Department, said in all, about 2,300 samples were collected from this year's deer season, an increase of about 1,000 from last year.

Deer hunters were asked to voluntarily drop off deer heads at selected locations in the state.

From there, Game and Fish Department workers removed what is called the retropharyngal lymph node, a gland near the deer's voice box in the throat.

Grove said Friday his department was in the process of wrapping up a few details before the samples will be sent to the Minnesota Veterinary Diagnostic Lab in St. Paul.

To date, there have been no reported cases of CWD in North Dakota.

CWD is a degenerative neurologic disease that affects deer, elk and moose.

It was first identified in mule deer at a wildlife research center in Colorado in 1967.

In 1985, it was detected in wild elk and wild mule deer herds, again in Colorado.

CWD has now been identified in wild deer and elk in six additional states: Illinois, Nebraska, New Mexico, South Dakota, Utah and Wisconsin.

CWD was detected in a farmed elk herd in South Dakota in 1997.

Since then, additional positive farmed elk and deer herds have been identified in South Dakota as well as seven other states: Colorado, Kansas, Minnesota, Montana, Nebraska, Oklahoma and Wisconsin, according to the U.S. Department of Agriculture.

Grove said the response from hunters, processors and taxidermists was exceptional.

"Basically, we received one sample from every hunting unit in the state," he said.

Grove said the Game and Fish Department has the state divided into six units for its surveillance program; this season, Units 3 and 4 were the focus of the program.

Those units roughly encompass the middle third of the state, from the South Dakota border to the Canadian border.

"We had a rough total of 964 samples from CWD Unit 3 and 693 samples from CWD Unit 4," Grove said.

"These numbers far exceeded our goals for the year. We had an additional 700 samples from outside this year's targeted area."

Grove said next year's surveillance will focus on the western portion of the state.

In addition, Grove said two hunting units in the northeastern portion of the state, 2C and 2D, were monitored not only for CWD, but for bovine tuberculosis as well.

While no cases of that disease have been confirmed in deer in North Dakota, it is an issue across the border in the northwestern portion of Minnesota.

Symptoms of CWD mirror those of other diseases, Grove said, and can include weight loss, poor hide condition, excessive salivation and coughing.

The incubation period for the disease is slow, so infected animals may not show visible signs for a number of years.

Grove said the department is expecting test results by the end of February.

(Reach reporter Brian Gehring 250-8254 or brian.gehring@bismarcktribune.com.)