About Elk Hoof Disease
Elk hoof disease is a debilitating disease that causes sores on the feet and deformed, overgrown, broken, or sloughed hooves. Affected elk are often observed limping or holding up a foot, as seen in these videos below. Sporadic cases of the disease may have occurred in southwestern Washington earlier, but in 2008 the number of limping elk with the condition dramatically increased.
Cause of disease
Scientific investigation determined spiral shaped bacteria known as Treponemes are present in affected feet so the disease is formally called Treponeme-associated hoof disease Treponeme-Associated Hoof Disease of Free-Ranging Elk (Cervus elaphus) in Southwestern Washington State, USA. It appears that these bacteria are spread through contaminated environments or from elk to elk by direct contact. However, these bacteria are likely not acting alone in causing the disease. Other factors such as overall animal health and nutrition, environmental factors, herbicides, and other disease causing organisms that may contribute to development of disease need to be investigated.
TAHD occurs in Roosevelt and Rocky Mountain elk of all ages and both sexes but has not been confirmed in other wildlife. Lameness and abnormal hooves in elk, deer, and other animals can be caused by a variety of diseases or injuries, so examination by specially trained veterinarians and laboratory tests are needed to diagnose TAHD. Cattle, sheep, and goats can have similar diseases, called digital dermatitis, that are also caused by Treponeme bacteria. We do not currently know if the diseases can be shared between livestock and elk. As a general practice, separation of wild and domestic animals is prudent as a preventative measure to reduce the risk of any disease spread. There is no evidence of humans contracting the disease. Humans are susceptible to some other Treponeme species which are different and cause other unrelated diseases.
The geographic range of the disease continues to expand with detection in most of the western counties in Washington and northern Oregon. More recently, cases have been detected in central Washington, western Idaho, southwestern Oregon, and northern California. Additional on-going monitoring is required to determine the extent of the disease, its spread over time, and to measure its impacts in these areas.
Elk hoof disease was first described as a local issue in southwest Washington. The disease is now a regional concern affecting elk in Washington, Oregon, Idaho, and California. Red crosses on the map indicate laboratory-confirmed cases of treponeme-associated hoof disease. Once the disease is confirmed in an area, additional laboratory testing may or may not occur, therefore, the number of crosses is not representative of the number of actual cases in an area. Shading indicates counties where a positive case has been confirmed. Data on this map came from cases submitted through the Washington Department of Fish and Wildlife, Oregon Department of Fish and Wildlife, Idaho Department of Fish and Game, and California Department of Fish and Wildlife. Laboratory testing was performed at several veterinary diagnostic laboratories including those at Washington State University, Colorado State University, and Oregon State University.
The impact of elk hoof disease on elk populations and natural systems is not known. The Washington Department of Fish and Wildlife (WDFW) reports that 20-90% of elk are limping in various herds in southwestern Washington. Preliminary results from WDFW research suggest that diseased elk have lower survival than their healthy counterparts, but additional study is needed.
TAHD infections are usually limited to the elk's feet. Treponeme bacteria have not been found in the meat of affected elk. However, other infections can occur and meat quality should always be evaluated prior to consumption. Additionally, safety guidelines should always be considered when handling, processing, and cooking wild game meat.
Why should I care?
Elk hoof disease affects everyone who cares about wildlife and our natural world. Hunters, wildlife viewers, and conservationists are well aware of the economic, social, recreational, ecological, and intrinsic value of healthy wildlife populations. Wildlife sometimes come into conflict with agricultural interests, and disease transmission between wildlife and livestock can be a significant concern when confirmed. Anyone concerned with animal well-being can’t help but have compassion for elk affected by this debilitating disease. And finally, all of us can benefit from understanding changes that are occurring in our environment that lead to issues such as emergence of new diseases. We all share a desire for healthy elk.