Bluetongue

Question 1

What kind of virus causes bluetongue disease?

Answer 1

Family - reoviridae

genus - orbivirus

Question 2

How does bluetongue present in sheep?

Answer 2

Fever
vasculutis
Edema, oral lesions, mucopurulent discharge
pulmonary edema
Hemorrhage and necrosis in muscles can cause lameness and heart failure
Coronitis, sore feet. Sloughing hoof.

Question 3

What are differentials for Bluetongue in sheep?

Answer 3

Contagious ecthyma (Orf)
FMD
Sheep pox
Other exotic diseases

Question 4

What is the vector for bluetongue?

Answer 4

Culicoides sonorensis - a midge that breeds in water/mud during the summer

Question 5

What is the seasonality of bluetongue?

Answer 5

Summer/Fall due to the presence of No-see-ums (Culicoides sonorensis)

Question 6

What teratogenic effects can bluetongue hav?

Answer 6

Sheep - Abortions, stillbirths, weak dummy lambs

Cattle - Cataracts, hydraencephaly, arthrogryposis, early fetal deaths

Question 7

How do we diagnose bluetongue?

Answer 7

Lab tests - ELISA, AGID, PCR

Clinical Signs

PM Lesions - widespread vasculitis and petechia. subendocardial hemorrhage at the base of the pulmonary artery is considered pathognomonic. Pulmonary congestion and subcutaneous edema.

Question 8

T/F - There is a vaccine for bluetongue

Answer 8

True! It is a MLV that contains serotypes 10, 11, and 17.

Note that pregnant ewes should NOT be vaccinated.