FORT COLLINS, Colo. – A study by state biologists shows that chronic wasting disease in northern Colorado strikes male deer at least twice as often as females in the same age groups.

The reason may be that males roam between herds looking for mates, said state Division of Wildlife veterinarian Mike Miller, who co-authored the study.

The study, published this month in the Journal of Wildlife Diseases, found bucks between 3 and 7 years old were 2.4 times more likely to be infected than does of the same age. Bucks 5 to 7 years old were 3.8 times more likely to be infected than does of the same age.

The disease appeared to peak in 5- to 6-year-old bucks and then sharply decline, an indication that the disease is fatal, Miller said.

Chronic wasting disease, a brain ailment that strikes deer and elk, is in the same family as mad cow disease. Officials say there is no evidence it can affect humans, but they advise against eating meat from infected animals.