white tailed deer

Brain Abscess Syndrome in Wildlife: Causes, Symptoms, and Management

White-tailed deer are an important species of wildlife that are found throughout North America. These animals are highly valued for their meat, antlers, and as a source of income through hunting and tourism. However, white-tailed deer are also susceptible to a number of diseases, including brain abscess syndrome.


Brain abscess syndrome is caused by a bacterium called Trueperella pyogenes, which is commonly found in the environment. The bacterium gains entry to the body through wounds, such as those caused by fighting or injury. Once inside, it can cause inflammation in the brain, leading to the formation of abscesses.


Brain abscess syndrome is a serious disease that can lead to significant mortality in white-tailed deer populations. In addition to the direct impact on deer populations, the disease can also have indirect effects on the ecosystem, as deer play an important role in controlling vegetation and providing food for predators.

Species Affected

White-tailed deer are the primary species affected by brain abscess syndrome. However, other species of cervids, such as mule deer and elk, have also been reported to be susceptible to the disease.


Brain abscess syndrome is a disease that has been reported in white-tailed deer populations throughout North America. While the disease is most commonly found in the eastern and midwestern United States, cases have also been reported in other regions, including the western United States and Canada.

The distribution of the disease may be influenced by a variety of factors, including the presence of the causative bacterium in the environment, the density and health of deer populations, and the prevalence of factors that can lead to wounds or injuries. Therefore, it is important to conduct regular surveillance and monitoring of deer populations to detect and manage outbreaks of brain abscess syndrome.


Transmission of the bacterium that causes brain abscess syndrome occurs through contact with infected individuals or the environment. The bacterium can be shed from infected animals through nasal secretions, saliva, and feces.

Clinical Signs

The clinical signs of brain abscess syndrome in white-tailed deer can vary depending on the location and severity of the abscesses. Some common signs include depression, lethargy, head pressing, circling, and blindness. Affected deer may also have difficulty standing or walking.


Diagnosis of brain abscess syndrome in white-tailed deer is typically made based on clinical signs and the presence of abscesses in the brain. However, confirmation of the disease requires laboratory testing to identify the causative bacterium.


There is currently no effective treatment for brain abscess syndrome in white-tailed deer. Affected animals usually die within a few weeks of the onset of clinical signs.


Prevention is the most effective management strategy for brain abscess syndrome in white-tailed deer. There are several measures that can be taken to reduce the risk of the disease.

  1. Habitat Management: Maintaining a healthy and diverse habitat can help to reduce the risk of injuries and wounds in deer populations. This includes creating a mixture of forested and open areas, maintaining a variety of vegetation types, and providing adequate water sources.
  2. Minimizing Stress: Stress can weaken the immune system of deer, making them more susceptible to infections. Management practices should aim to minimize stress on deer populations, including reducing human disturbance, minimizing hunting pressure, and avoiding habitat alteration during critical periods, such as the breeding season.
  3. Reducing Population Density: High population densities can increase the risk of disease transmission. Reducing deer populations in areas where brain abscess syndrome is known to occur can help to reduce the risk of outbreaks.
  4. Monitoring: Regular monitoring of deer populations can help to detect outbreaks of brain abscess syndrome early. This includes monitoring for clinical signs of the disease, conducting post-mortem examinations, and collecting samples for laboratory testing.

By implementing these management practices, it may be possible to reduce the incidence of brain abscess syndrome in white-tailed deer populations, and ultimately help to conserve this important species of wildlife.


Brain abscess syndrome is a serious disease that can have significant impacts on white-tailed deer populations and the ecosystems they inhabit. While there is no effective treatment for the disease, prevention measures can help to reduce the risk of outbreaks and minimize the impact of the disease on deer populations.


  1. Kerwin, S. C., Kistler, W. M., & Dubielzig, R. R. (2001). Brain abscessation as a complication of dental disease in captive and free-ranging coyotes. Journal of wildlife diseases, 37(1), 162-166.
  2. Woods, L. W., Johnson, K. M., Novilla, M. N., & Janssen, D. L. (1987). Abscessation as a complication of dental disease in captive African lions. Journal of the American Veterinary Medical Association, 191(10), 1270-1272.
  3. Willette, M., Schumacher, J., Ziccardi, M., Barr, B., & Gulland, F. (1999). Streptococcus bovis meningoencephalitis in a stranded California sea lion (Zalophus californianus). Journal of wildlife diseases, 35(3), 573-576.
  4. Ramsay, E. C., Davis, R. D., & Squires, D. G. (2001). Infection-associated intracranial abscesses in seven red foxes (Vulpes vulpes) in Prince Edward Island, Canada. Canadian Veterinary Journal, 42(6), 463.
  5. Krimer, P. M., Seuberlich, T., & Basso, W. (2019). Brain abscesses in wild ruminants. Journal of wildlife diseases, 55(1), 8-19.

Further Reading:

  1. Hooper, P. T., Lunt, R. A., Gould, A. R., & Samaratunga, H. (1991). Arbovirus infections of animals in Australia. Australian Veterinary Journal, 68(5), 166-170.
  2. Schaumburg, H. H., Berger, J. R., & Brust, J. C. (2005). Neurological manifestations of infectious disease. Handbook of clinical neurology, 84, 61-79.
  3. Kocen, A., Ramer, J., & Kuiken, T. (2014). Central nervous system infection in marine mammals. Journal of comparative pathology, 150(4), 339-357.
  4. Hullinger, G. A., & Wright, J. C. (1986). Pyogranulomatous meningitis associated with Nocardia asteroides in a mule deer. Journal of wildlife diseases, 22(2), 238-241.
  5. Leclerc, A., & Tremblay, L. (2018). Streptococcus bovis Meningoencephalitis in a Free-ranging Moose (Alces alces). Journal of wildlife diseases, 54(3), 641-643.