Agriculture Reference
In-Depth Information
Bluetongue:
Bluetongue is indistinguishable from foot and mouth disease and is therefore a
reportable disease. Foot and mouth disease is a serious illness in sheep and cattle. It is import-
ant to differentiate bluetongue from foot and mouth disease, as currently foot and mouth dis-
ease is not present in the United States. If it is discovered in the United States, all exports of
livestock from the country will cease, and all affected animals will be slaughtered. All sheep
exhibiting the signs of bluetongue/foot and mouth disease need to be reported. Testing will be
performed on the sheep to determine which disease is affecting the sheep.
Biting insects transmit the bluetongue virus from sheep to sheep. There are two clinical dis-
eases of sheep: reproductive disorders and a vasculitis disease of several different organ sys-
tems. The vasculitis disease causes fever, facial edema, salivation, nasal discharge, oral ulcers,
reddened nose or mouth, pneumonia, lameness and stiffness, and death. Reproductive disease
can manifest as dummy lamb births, miscarriages, or stillbirths. A dummy lamb is a lamb that
does not suckle, seems slow, is weak at birth, and may not have a good chance of survival.
Prevention revolves around controlling the vectors (insects) of the disease. Using insecticides
around the barn, prompt removal and proper disposal of manure, draining of stagnant water,
and using insecticides on sheep will help to reduce the number of biting insects.
Pizzle rot:
Pizzle rot, or balanoposthitis, is a common condition in wethers (castrated male
sheep) and less so in rams. High protein levels, especially when caused by feeding on rich
pastures, produce a urine rich in urea, a waste product the body produces from protein meta-
bolism. The alkalinity of the urine makes an ideal growth medium for bacteria, such as
Corynebacterium renale
, which is the primary culprit in pizzle rot although other bacteria can
cause the condition as well. The bacteria interact with the urea in the urine to produce ammo-
nia. Strong ammonia can scald the prepuce and surrounding area, leading to necrosis of the
tissue. Scarring and stricture formation can block the urine flow and lead to retention of urine.
Keeping the belly and prepuce closely shorn will help urine dry quickly. If the condition is
caught early, removing the rich feed sources is successful at resolving the condition. Later
stage treatment is rarely successful as there will be extensive damage to the urinary tract that
will be impossible to correct or reverse.
Orf:
A virus causes contagious ecthyma (Orf). The most common sign is shallow ulcers that
appear in the lip, nostril, and feet areas. Lambs are most commonly infected and may be re-
luctant to nurse due to mouth and nose lesions. Lambs might spread the disease to unvaccin-
ated or unexposed older animals.
