Be on the lookout for EHD in Deer this Fall

2975135737_aa83f40c3c_zThere have been some sightings of deer that may have Epizootic Hemorrhagic Disease (EHD) in the MidMichigan area.  Although these cases are speculative it seems to be happening earlier this year than in 2013.  This is a reminder if you notice any EHD behavior in deer please report it to the DNR.  If you need a refresher of the symptoms and behaviors exhibited by EHD infected deer details are shown below along with numbers from the 2013 season brought to you by the DNR.

 

2013 Summary:
In 2013, EHD has been diagnosed in 7 deer in 6 counties. The laboratory confirmed deer are from Muskegon, Ottawa, Oceana, Ionia, Berrien, and Allegan counties. Small numbers of additional dead deer were reported associated with these mortalities. Total mortality estimates at this point are difficult to determine; final figures will be determined following the completion of the firearm deer season. It appears that the estimate will likely be in the 100 to 400 deer range.

 

Transmission and Development:
The mode of transmission of EHD in nature is via a Culicoides biting fly or midge. Culicoides variipennis is the most commonly incriminated vector in North America. A deer must be bitten by a midge carrying the virus to become infected. The disease is not transmitted directly from one deer to another but must go through the insect vector. A common observation in outbreaks involving large numbers of deer is that they are single epizootics which do not recur. Die-offs involving small numbers of deer occur almost annually, and the disease appears to be enzootic in these areas. All documented outbreaks of EHD have occurred during late summer and early fall (August-October) and have ceased within two weeks of the onset of frost, which kills the midge.
Experimentally, the disease can be transmitted to susceptible deer by the inoculation of virus-laden material from infected deer by subcutaneous, intramuscular, intravenous or oral routes.

 

Clinical Signs:
Clinical signs of EHD and bluetongue are very similar.
White-tailed deer develop signs of illness about 7 days after exposure. A constant characteristic of the disease is its sudden onset. Deer initially lose their appetite and fear of humans, grow progressively weaker, often salivate excessively, develop a rapid pulse and respiration rate, and fever (affected animals frequent bodies of water to lie in to reduce their body temperature) and finally become unconscious. Hemorrhage and lack of oxygen in the blood results in a blue appearance of the oral mucosa, hence the name 'bluetongue'. Eight to 36 hours following the onset of observable signs, deer pass into a shock-like state, become prostrate and die. More photos of dead deer in water with permission from Tom Stafford of QDMA.com

 

Pathology:
The gross and histological lesions of EHD have been characterized by, as its name implies, extensive hemorrhage. The hemorrhages range from pinpoint to massive in size, and involve different tissues and organs in individual animals. No organs appear to be exempt from hemorrhage, with the most regularly involved being the heart, liver, spleen, kidney, lung and intestinal tract. Extensive hemorrhaging is the result of interference with the blood-clotting mechanism together with degeneration of blood vessel walls.
Generalized edema and increased pericardial fluid are consistently found in EHD. These changes also reflect the widespread interference with normal blood circulation.
The virus can be recovered from a variety of tissues of animals which have succumbed to EHD. These include blood, liver, spleen, kidney, lung, heart and muscle.

 

Lastly, Information for Hunters, What to look for in your deer:

Hoof Abnormalities
EHD lesions seen in dead deer
Even with these lesions, the deer meat is edible. If you see any of these please take your deer to a MDNR Check Station.If you come across dead deer in the field, please report them by following these directions:
To report the presence of dead deer, we encourage members of the public to contact their nearest MDNR Wildlife office or fill out the Sick or diseased bird or mammal Reporting Form. If you have specific information that has been reported to you but that has not yet been shared (not first hand), you may report it on the same form. The form requests a zip code; if you don't know the zip code of the location of the suspect EHD deer, just enter 55555. Thank you.

For the entire article from the DNR follow the link below:
http://www.michigan.gov/dnr/0,1607,7-153-10370_12150-26647--,00.html

 

Be the first to comment

Please check your e-mail for a link to activate your account.