Bluetongue Disease in Sheep and Goats

Bluetongue Disease in Sheep and Goats:

About this disease

• This is acute infectious but not contagious disease of sheep characterized by fever, inflammation and ulceration of buccal mucosa and tongue.
• This disease mostly affects sheep and goat and cattle are very rarely affected.
• Blue tongue is endemic in India.
• It is basically a disease of sheep and young sheep within the age group of one year are more prone to infection.
• Suckling lambs are relatively resistant due to their acquired passive immunity through colostrum.
• The disease occurs mainly during the rainy season particularly in the months of October, November and December.

What Causes Bluetongue  Disease?

• It is caused by Arthropod-borne orbi virus in the family of Reoviridae.
• Biting insect of the genus of the Culicoides transmits the virus during the rainy season while blood sucking.
• Mosquitoes and other ectoparasites like sheep ked, Melophagus ovinusmay transmit the disease mechanically.
• The disease is more prevalent in late summer and early autumn which makes conducive environment for the multiplication of the vectors.
• Transmission through semen and placental route is possible.
• The virus is resistant to decomposition, desiccation and against antiseptic agents.

What are the symptoms of BT ?

• Fever
• Depressed attitude and off feed.
• Reddening and swelling of nose and oral mucosa,
• Profuse nasal and oral discharge,
• Inflammation and ulceration of lips, gums,  buccal mucosa and tongue,
• Cyanotic (bluish) appearance of tongue,
• Tilting of neck towards one side (wry neck)
• Lameness, reddening and swelling of coronary band of the limbs.
• Congestion of conjunctival mucous membranes and matting of eyelids,
• Foul smelling diarrhoea.
• Dyspnoea, snoring and Pneumonia may be observed.
• Death due to respiratory failure.

First aid for Bluetongue  Disease in Sheep and Goats:-

• Separation of sick animals should be made.
• Affected animals should be kept away from solar exposure.
• Adequate rest to the affected animal.
• Affected animals should be fed with porridge made of rice, ragi and kambu.
• Apply glycerin or animal fat on the ulcers.
• Immediate consultation should be made to the nearest qualified veterinary doctor for treatment.
• Animals should not be allowed for grazing.
• Ulcers in the mouth can be treated with saline water or dissolve 1g of

Potassium permanganate in 1 liter of water and wash the mouth 2 to 3 times a day with this solution.

• Contact your nearest Veterinary Assistant Surgeons for further advice regarding the antibiotic administration or symptomatic treatment to be given to the affected sheep.
• Contact nearest Veterinary Assistant Surgeons for ring vaccination in the event of outbreak of disease.

General prevention and control measures

• Proper Vaccination of animals with regular intervals.
• Vaccination schedule:

• Attempt should be made to control the vector (culicoides) population with fly repellants.
• Use of ectoparasiticides injections should be suggested in the areas more prone to vector population.
• Grazing of the animals should be avoided in areas where there is lot of vectors.
• Cattle may act as carrier. Viraemic stage remains in them for more than 5 weeks. So movements of cattle should be restricted.
• Importation of animals from the areas prevailing the disease should be avoided.
• Strict regulation is to be followed to prevent entry of diseased animals from endemic zones.
• The spread of the disease can be controlled by the use of insect repellents, external application of fly repellents and spraying of butox (1ml in 1 liter of water) in the breeding places of the insects.
• The sheep can be housed in insect proof sheds.
• Cloud of smoke with dried leaves / wood during 6 – 8 P.M. might help to keep off Culicoides from sheep sheds.

Courtesy By Tamil Nadu Agricultural University @ www.agritech.tnau.ac.in/