New York State Borders

By: Gail Veley • Sponsored by NYDEFA

New York deer farmers would be wise to do a risk assessment to determine their whitetail deer herd’s susceptibility to contracting EHD (as well as the related virus Blue Tongue.) With EHD having been confirmed this year in wild populations of whitetail deer in

New York, a collective concern over what potential steps to take next is on the minds of many deer farmers, said

New York Deer and Elk Association

President Dave Vanderzee. Although

EHD was typically thought of as a disease only affecting southern states, changing weather patterns, above normal rainfall, strong winds and higher air masses in the past year carried the gnat-like culprit for

EHD, the Culicoides midge fly, over the Adirondack Mountain range and into New York where it could begin to substantially affect deer farmers. To date, there is no cure for the 10 known strains of EHD, and no treatment plan for wild deer.

A concentration of sick wild deer found living along the Hudson River in Ulster County in late July, tested positive for EHD Strain 6, according to Kevin Hynes, Wildlife Disease Biologist with The New York Department of Environmental Conservation. Wildlife staff and officers within the department are keeping a vigilant watch in an effort to continue EHD testing and responding to reports of sick deer.

Epizootic Hemorrhagic Disease (EHD) affects the endothelium or the lining of the blood vessels, causing hemorrhagic and respiratory distress in addition to ulcers on the tongue, nasal cavity and stomach. Clinical signs appear in one to three days and include reduced appetite, weakness, a loss of the fear of humans, fever, edema, swollen eyelids, neck or tongue and the internal drive to stay close to and drink water. Although EHD is a common concern year-round in temperate southern states such as Florida and Louisiana, it was not seen until recently as a threat to whitetail deer living as far north as New York. Yet unlike southern states, the midge fly has a short-lived life span in New York, where the first annual October or November frost kills them off.

However, this advantage does only so much in staving off a disease that’s most often fatal to whitetail who fall prey to the bite of the Culicoides midge fly who lives, breeds and thrives along muddy riverbanks or swampy areas. Those deer that do survive show hoof abnormalities in later months. Adding an EHD vaccine program to a New York deer farmer’s maintenance and care protocol may be worthwhile, depending on the lay of your land and where you keep your deer, Vanderzee emphasized.

According to website information provided through The New York Department of Agriculture and Markets, New York contains 7,342 square miles of inland waters as well as portions of Lake Erie and Lake Ontario. Seventeen major watersheds provide the venue for more than 4,000 lakes, ponds and 70,000 miles of streams, all of which could potentially provide a home to the midge fly. This is where the risk assessment for your deer farm comes into play.

“Deer farmers should pull out soil and water maps available through The New York Division of Soil and Water and take a detailed look at them,” Vanderzee said. According to what is found, informed decisions could be made regarding vaccines, he explained. And while other preventative measures such as installing insecticide misters or putting up shade cloth on existing fences to block the flight of the Culicoides (whose flight trajectory is a mere three feet from the ground), the vaccine might provide the best overall protection, he added, placing perhaps an additional unwelcomed burden and expense upon New York deer farmers.

Farmers who choose to vaccinate must follow strict guidelines including deciding which of the 10 strains of EHD to vaccinate for, and subsequently have it shipped to the veterinarian on file or associated with your deer farm. An initial vaccine must be followed by a booster shot within eight to 10 days. “It can be difficult to choose a convenient time to do this,” Vanderzee said. “You want to wait until it’s cool and when the bucks aren’t in velvet or in the rut. And not all deer handle the capture process well. Giving them a vaccine isn’t always a very clear ‘risk and reward’ situation. And would you have even vaccinated for the right strain? Is it better to just dodge bullets or mitigate certain areas of your farm? Being prepared to take action will be our best form of defense, as we see the way EHD plays out in New York in the months that lie ahead.”