deer disease | Buck Manager

Lumpy Jaw in White-tailed Deer

Lumpy Jaw

The white-tailed deer hunting season sneaks up on us each year. Most hunters are already in the woods looking for a big, mature buck. Hunters often see some strange things while in the woods. Have you ever seen lumpy jaw in deer? Sometimes, those odd things include deer afflicted with a variety of diseases and other internal and external physical issues.

One fairly common problem in whitetail is lumpy jaw. The name “lumpy jaw” says it all because deer with this problem stick out; The animal looks like it has a lump between (or under) its jawbone and the hide. The lumpy jaw many hunters witness is the result of adult arterial nematodes (Elaeophora schneideri). These worms live primarily in the whitetail’s carotid arteries. In fact, partial paralysis of the deer’s jaw muscles occurs when high arterial worm infestations reduce blood flow.

Whitetail Deer Management: Lumpy Jaw in Whitetail Deer

Impact of Lumpy Jaw

An overabundance of arterial worms is bad news for deer. As a result of jaw muscle paralysis, food becomes trapped inside the deer’s mouth. This food becomes impacted and leads to the lumpy jaw and/or swollen cheek appearance. Over time, the impaction often causes tooth loss, bone decay, and sometimes even death.

So now your thinking, how do white-tailed deer get lumpy jaw? Good question! The common horsefly passes the nematode larvae from an infected deer to an uninfected one by feeding on deer blood. The horsefly carrying larvae-infected blood is ultimately what perpetuates this lumpy jaw condition in deer.

Deer Management: Lumpy Jaw in Whitetail Deer

Lumpy Jaw & Deer Populations

Lumpy jaw in deer is widespread, but it poses little threat to deer populations. Luckily for property owners, hunters, and the deer, infection rates in are not high enough to impact white-tailed deer populations. Arterial worms, like most other deer issues, do not pose a risk to humans. Hunters can consume deer that exhibit lumpy jaw. Many deer have arterial worms and show no symptoms, so you’ve eaten deer with arterial worms.

However, as a hunter I don’t like to think it too much. Who wants to think about arterial worms, nasal bots, or any other of the many diseases, viruses, or things deer can possibly tote around?

Deer Management: Lumpy Jaw in Whitetail

More Lumpy Jaw in Deer?

Arterial worms are not the only game in town. Other creatures can give white-tailed deer that lumpy jaw appearance. A bacterium called Actinomyces bovis can also cause an infection of the jawbone. This bacterium is actually a common inhabitant of the mouths of healthy whitetail. It is only a problem when a sharp object such as a thorn punctures the inner lining of a deer’s mouth. This oral puncture allows A. bovis bacteria to invade the tissues.

Additionally, healthy deer — like all animals — can simply get large or odd-shaped food items caught in their mouth. However, food impaction in white-tailed deer is most often the result of arterial worms. This results in muscle issues that lead to food impaction and lumpy jaw syndrome. As mentioned, lumpy jaw in deer does not pose a health problem for hunters. The meat can be safely consumed.

White-tailed Deer Warts

A deer hunter never expects to see giant warts or tumor-like growths on a white-tailed deer, but they do occur. Over the years I’ve seen many of photos of both live and harvested deer with “tumors,” although I’ve never seen one while in the field. The technical term for these growths is cutaneous fibroma and it’s caused by a virus. From a deer management perspective, there is not much you can do to keep wild deer from getting fibroma.

What are External Deer Tumors?

First, they are not tumors at all — they’re warts. Cutaneous fibromas are caused by a naturally occurring virus of the deer’s skin. The virus that causes these unsightly warts in deer is believed to be transmitted through biting insects and/or direct contact with damaged skin. Once the virus enters the skin, warts begin to form.

As the warts increase in size, the skin surrounding them is typically hairless and grayish in color. The number of warts on an infected animal can vary from one to several hundred, they can sometimes clump, and can in some cases end up covering much of the deer’s body.

Do Warts Bother Deer?

For the most part, these warts will not cause a white-tailed deer any major problems. However, sometimes the growth of the wart can indirectly cause problems by restricting the consumption of food or the deer’s breathing depending on where the growths are located.

Although death from fibromas in deer can occur, death from warts is not always imminent it seems. There have been many hunter testimonials of white-tailed deer with warts “shaking them off,” so to speak. In those cases, where they really the same deer? I can’t say for sure. I could see a situation where a deer with an isolated wart could recover, so to speak.

Deer Warts, Deer Hunting

From a deer hunter’s perspective warts are quite unsightly. Since fibromasts are a virus of the skin, they will be removed if the deer is skinned. Notice I said IF the deer is skinned. Although the meat of a deer is typically not affected, most hunters that harvest a deer with a large number of warts are hesitant to put the meat in the freezer.

This is understandable and probably the safest thing to do. Some research reported that a buck with external warts also had internal and cancerous fibromasts. Again, if an animal does not appear healthy then use your own, conservative discretion.

The take home message on warts is that they do occur naturally in white-tailed deer across their range. Fibromasts can occur on any deer, healthy or otherwise. With that said, these warts occur rather rarely and there is nothing that can be done from a deer management standpoint to manage against them. Deer are the only host for the virus, so fear not for yourself should you find yourself standing over an infected, wart-covered animal.

The Spread of CWD in White-tailed Deer

Serious diseases such as chronic wasting disease (CWD) can be detrimental to whitetail deer management programs with mortalities impacting local deer numbers as well as regional and potentially even statewide deer populations. State agencies around the country have been monitoring CWD in deer herds for many years now, and they know that it is caused by prions, but much about the spread of the disease was unknown until now. Researchers have discovered that deer asymptomatic for the fatal brain condition known as CWD excrete the infectious prions that cause the disease in their feces.

The finding suggests a reasonable explanation for transmission of the disease among white-tailed deer, mule deer, and possibly elk and moose in the environment. While the study reveals that prions are shed in feces of symptomatic deer as well, the discovery that the infected deer shed prions in their feces many months before they show clinical symptoms is the most unsettling. White-tailed deer, mule deer, elk and moose inadvertently consume feces and soil in the course of their daily browsing and grazing.

The prion is an infectious form of the normal prion protein, which has been found in all mammals examined, including humans. The lethal, infectious form induces the normal protein to twist into a malconformation, initiating a disease process that ravages the brain. Prion diseases, seen in cervids, sheep, cows and humans, are also referred to as spongiform encephalopathies. In wid and captive deer, researchers now know that the inadvertant consumption of feces is how the disease is transferred from animal to animal. So what’s the next step?

With this information in hand, the researchers set out to determine whether the animals could develop chronic wasting disease through long-term consumption of contaminated feces. They did so by measuring the amount of prions contained in the feces of orally infected deer up until the time they became symptomatic and then calculated whether prolonged exposure to the concentrations of prions in these feces would be enough to cause the disease.

“Prion levels in feces samples of asymptomatic deer were very low compared to those in the brains of the same deer at the time of death,” says the lead author of the study, Erdem Tamguney, PhD, an assistant professor at the Institute for Neurodegenerative Diseases, based at UCSF. “However, the total number of prions excreted over time was sufficiently high enough to cause disease in other deer.”

The susceptibility of animals to infection, he says, may also be increased by the simultaneous ingestion of clay soil, which is thought to enhance the infectivity of prions, possibly by slowing their clearance from the gastrointestinal tract.

“Our findings suggest that prolonged fecal prion excretion by infected deer provides a plausible explanation for the high level of transmission of chronic wasting disease within deer herds, as well as prion transmission among deer and other cervid species. Our work may also explain transmission of scrapie prions among sheep and goats,” says senior author and Nobel laureate Stanley B. Prusiner, MD, UCSF professor of neurology and director of the UCSF Institute for Neurodegenerative Diseases.

The study did not examine whether CWD could be transmitted to humans via exposure to deer feces. To date, transgenic mouse studies have indicated that chronic wasting disease does not transmit to humans, but scientists remain open to the possibility that it could.

“We can only say that prions of chronic wasting disease have not transmitted to mice genetically engineered to carry the normal, healthy form of human prion protein in earlier studies,” says Prusiner. “That said, we do not know for sure that deer or elk prions cannot be transmitted to humans.”

Chronic Wasting Disease Monitoring Continues

State wildlife departments across the United States have continued with their annual Chronic Wasting Disease (CWD) monitoring in wild deer populations. Although numerous research studies are underway, there is currently no vaccine or other biological method of preventing CWD in a free-ranging deer herd. The only tool wildlife biologists and hunters have is to prevent the spread of CWD to new areas, because once an infected prion is deposited into the environment through either an infected carcass or from a live deer, it can remain viable for a decade or more!

Texas Parks and Wildlife Department (TPWD) wildlife biologists and technicians have continued their annual testing of tissue samples (brain stems) from hunter-harvested and road-killed white-tailed deer during the 2008-09 hunting season. To date, Texas has had no documented case of CWD within the State. Many of the samples collected over the hunting season are being prepared for analysis at the Texas Veterinary Medical Diagnostic Laboratory at Texas A&M University in College Station, Texas.

Although CWD has yet to be found in Texas, three hunter-harvested white-tailed deer in Kansas have tested positive for CWD in recent weeks according to the Kansas Department of Wildlife and Parks (KDWP). In the past few years, numerous cases of CWD have been documented in other states located in the central part of the U.S., including Oklahoma, New Mexico, Colorado, Nebraska, and Wyoming.

CWD is a progressive and fatal disease that results in small holes developing in the brain, giving it a sponge-like appearance under a microscope. Decreased brain function causes white-tailed deer, mule deer, and elk to display neurological symptoms such as depression, a droopy head, staggering, loss of appetite, and a lack of response to human disturbance. The continuing deterioration of the brain leads to other symptoms such as weight loss, drooling, and excessive thirst. If hunting in an area where CWD is known to exist, caution is advised. With that said, no human health risks have been discovered where CWD occurs.

The symptoms of CWD in deer include loss of body weight, stumbling, holding the head at an odd angle, circling, non-responsiveness to people, and pneumonia. Hunters can help protect the health of their local deer herd by taking the following steps to avoid accidentally transmitting CWD to new areas. First, do not transport deer carcasses far from the area where the deer lived, especially from areas where CWD has been detected. Secondly, if a deer carcass is transported, the hunter should make sure that carcass waste is not dumped in a location where other deer can come into contact with it. Carcass waste can also be disposed of by bagging and taking it to a landfill.

Blue Tongue in White-tailed Deer

Blue tongue is an insect-borne, viral disease primarily of sheep, but it occasionally goats and even white-tailed deer. The disease is non-contagious and is only transmitted by insect vectors, especially during periods of drought. The disease is actually caused by a virus belonging to the family Reoviridae.

Species That Can Be Affected

As mentioned, this is primarily a disease of sheep but other species such as goats, cattle, buffalo, antelope and whitetail deer can be infected. Don’t worry, humans can not be infected.

Distribution of Blue Tongue

The virus is present in the United States, so any area can potentially harbor the virus. However, outbreaks typically occurs repeatedly in areas where it has occurred before and especially during dry conditions.

Key Signs To Look For

Characters of disease include fever, widespread bleeding of the oral and nasal tissue, excessive salivation, and nasal discharge. In acute cases the lips and tongue will become swollen and this swelling may extend below the lower jaw.

Lameness, due to swelling of the cuticle above the hoofs and emaciation, due to reduced feed consumption because of painful inflamed mouths, may also be symptoms of this disease. The “blue tongue” that actually gives the disease its name occurs only in a small number of cases.

How Blue Tongue is Spread

The virus cannot be transmitted between susceptible white-tailed deer without the presence of insect carriers. The incidence and geographical distribution of bluetongue depends on seasonal conditions, the presence of insect vectors, and the availability of the density of deer. The insect carriers, biting midges, prefer warm, moist conditions and are in their greatest numbers and most active after it rains.

Life of the Blue Tongue Virus

Bluetongue virus does not survive outside the insect vectors or susceptible hosts. Deer carcases and products such as meat and hide are not a method of spread. Survival of the virus within a location is dependent on whether the vector can over winter in that area.

Controlling Blue Tongue

Within a wild population of deer, there is not much that can be done. With domestic animals, you can use a combination of quarantine and movement controls to prevent spread and reduce transmission and protect susceptible animals. As with just about every disease, less animals will become infected under lower densities.