Bluetongue confirmed in Wyoming
In flocks of sheep in the Bighorn Basin
by Wyoming Livestock Board
October 19, 2007
(Cheyenne) - The Wyoming Livestock Board and State Veterinarian, Dr. Walt Cook, report that Bluetongue has been confirmed and reported in three flocks of sheep in the Bighorn Basin. According to the Wyoming State Veterinary Laboratory, seven (7) cases of the disease have now been diagnosed in North-central Wyoming. Significant death-loss has occurred in at least two flocks and many sheep are showing clinical signs in other flocks. Quarantines have been imposed on confirmed and reported premises.
Bluetongue is a reportable disease in Wyoming. Livestock owners and veterinarians who are aware that the disease exists in animals under their care are required to report this to the Wyoming State Veterinarian by calling: 307-777-6443.
Bluetongue is a viral disease that is transmitted by biting insects; primarily the Culicoides gnat. The disease is not contagious from one animal to another. Bluetongue can affect sheep, goats, cattle, and wild ruminant species. It is primarily of significance in sheep, deer, and antelope.
After an incubation period of 5 to 10 days, an infected animal will go off feed, develop a high fever, depression, and difficulty in breathing. Signs may also include inflammation and swelling of the oral tissues and tongue, lameness, head tilt, and pneumonia. Mortality may range from 0 to 30% of affected animals.
In deer and antelope, the virus often causes a sudden fatal hemorrhagic disease. Also, in wildlife, Bluetongue is very similar to Epizootic Hemorrhagic Disease which can also be fatal and may be endemic in certain areas. The Wyoming Game and Fish Department has recently documented wildlife cases of Bluetongue in the Worland and Douglas areas.
The disease is mainly a warm weather problem due to the insect vectors. Prevention and control consist mainly of measures to prevent insect bites on susceptible animals and environmental spraying for insects. A vaccine is reportedly available in the United States, but it has limitations and side affects that make its use of questionable value.
Bluetongue transmission from the insect vectors should subside with a hard frost. Treatment consists of supportive therapy such as anti-inflammatories, vitamins, and fluids. The virus will remain in an infected animalís bloodstream for up to 10 days.
For more information about Bluetongue in Wildlife, you may contact either Drs. Tate or Cornish and for Bluetongue in Livestock either Drs. Bratanich or Montgomery at the Wyoming State Veterinary Laboratory, 307-742-6638.