Buck Manager: Disease & Virus


Precautions for Processing Deer »

Deer Disease: Take Caution During Deer Processing

Deer hunting is both challenging and fun, but common sense precautions while handling a processing white-tailed deer should be taken after each successful harvest. In fact, proper handling and cleaning techniques are as important as sound deer management practices. Many diseases affect deer in North America, including rabies, tularemia, plague, blue tongue and potentially even chronic wasting disease (CWD). CWD is a disease that affects white-tailed deer, black-tailed deer, mule deer, and elk and is fatal to infected animals.

Biologist believe a protein called a prion causes CWD in deer, and it’s this disease that most hunters are probably worried about. Prions concentrate in the brain, spinal cord, eyes, lymph nodes and spleen. Prions have not been found in meat or muscle tissue. According to the researchers, there is no evidence that chronic wasting disease can be transmitted to humans. (more…)

White-tailed Deer Warts »

White-tailed Doe with Fibromasts

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.

Cutaneous fibromas (warts) 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. (more…)

Nasal Bots in White-tailed Deer »

White-tailed deer often have nasal bots

Most hunters that have harvested any number of white-tailed deer have unfortunately found nasal bots. At first glance, what a hunter encounters looks like a large maggot. And it basically is, and they live in the cavities of the nose and mouth. Nasal bots are the larvae of a specific kind of fly that belongs in the genus Cephenemyia. Deer biologists actually find them in a high percentage of whitetail deer, particularly when a thorough examination of the head is conducted. From my experience, white-tailed deer in Texas are much more likely to have nasals bots than not.

These bots are specific to members of the deer family, which also includes elk and mule deer in the United States. Nasal bots begin life when the adult fly lays a group of eggs around the nose or mouth of a deer. The small larvae within these eggs are then released when the deer licks the eggs. The warm, wet saliva creates an environment that permits the “hatching” of the immature bots. These larvae then migrate to the nasal passages and occasionally into the sinuses where they molt into larger stages of the maturing larvae. (more…)

The Spread of CWD in White-tailed Deer »

Chronic wasting disease (CWD) is spread through deer feces

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. (more…)

Chronic Wasting Disease Monitoring Continues »

Map of known CWD locations

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. (more…)

Deer Warts or Tumors? »

When deer hunters head out into the field they don’t usually think to themselves, “Man, I want to harvest a healthy deer.” But we all do, even though we don’t directly think about it. What if you harvested a deer with warts? Well, most hunters would be a little concerned, because after all, warts are not normal on white-tailed deer. Although injuries and diseases are something that landowners serious about deer management try to avoid having in their herd, it usually can not be avoided.

These “deer tumors”, which are more accurately wart-like growths, and are formally referred to as cutaneous fibromatosis. The virus that causes such growth on the skin can be transmitted between deer, at least experimentally. Deer fibroma occurs occasionally in white-tailed deer living in North America. Although the ailment is not common, it not extremely rare either. The cutaneous growths can vary in diameter, but usually vary from about 1/4 inch to 4 inches in size. (more…)

Supplemental Feeding and Disease Transmission in White-tailed Deer »

Supplemental Feeding and Disease Transmission

Question: A friend and I are considering starting a supplemental feeding program for the white-tailed deer population on his farm where we hunt. Our goal is to, over time produce larger, healthier bucks and does, as well as attract and holding a larger population of high-quality animals for hunting.

We are planning to implement food plots as the main approach to this end, but we are also considering supplemental feeding during the winter, when the does are carrying fawns and the bucks are shedding and preparing for the growth of the coming years antlers.

In my research on supplemental feeds, have I found several articles suggesting that supplemental feeding increases the chances of the transmission of diseases like ‘blue tongue’, which is normally associated with deer using the same watering hole as an infected animal. (more…)

Blue Tongue in White-tailed Deer »

Bluetongue 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.