Ticks, other factors tied to cattle, deer deaths
PIERRE, S.D. (AP)--Ticks, severe weather and other factors appear to have contributed to the deaths of cattle, horses and deer in an isolated area of southwestern South Dakota, acting State Veterinarian Dustin Oedekoven said April 16.
After the Animal Industry Board received calls about unexplained animal deaths in an area south of Interior, local veterinarians worked with laboratories to seek a diagnosis, Oedekoven said. It appears that a number of factors including ticks, snowstorms and a lack of nutrition contributed to cattle deaths, he said.
A heavy infestation of ticks was found on many of the animals, Oedekoven said. The species is known as the winter tick and can be found on deer, elk and cattle. Ticks were part of the problem, but probably not the main cause of death among cattle, the veterinarian said.
Ticks can cause cattle to become weak so they are more susceptible to the cold and blowing snow that have hit the area, particularly if the animals don't have sufficient nutrition, Oedekoven said. Pregnant cows need adequate nutrition because they are carrying calves and preparing for birth, and the period before calving includes some of the harshest winter months, he said.
"All factors combined seemed to be enough to put some of these cows over the top," the veterinarian said.
Some people were worried about anaplasmosis, a tick-borne disease that causes anemia, but that disease has not been identified in any samples from the dead cattle, Oedekoven said.
"There seemed to be so many rumors, especially people concerned that the deer were giving something to the cattle. There doesn't seem to be any proof to that."
About 20 ranchers in the area reported some cattle deaths, Oedekoven said. State officials sought information from other veterinarians in the area, but got little response.
"If this were an outbreak of some kind, we would have expected to have a lot of people calling in and reporting ticks and dead or dying animals. It looks like it's fairly isolated in that area," he said.
Bad snowstorms and flooding have been problems in much of western South Dakota, causing a lot of livestock loss during the winter, Oedekoven said. Reports indicate some ranches have lost as much as 10 percent of their cattle, he said.
Farmers and ranchers should contact a local veterinarian anytime they notice something unusual, such as increased deaths or a lot of parasites on livestock, Oedekoven said.
People who see sick or dead deer and other wildlife are encouraged to contact the nearest state Wildlife Division office or local conservation officer.