LIP-AND-LEG ULCERATION OF SHEEP 273' 



cheeks may also be involved or even the eyelids. Occasion- 

 ally the mucous membrane of the nose and mouth is invaded. 

 Quite commonly lesions occur on the legs. The favorite 

 seat is about the coronet, under the fetlock or in the neighbor- 

 . hood of the fetlock-joint. The ulcers upon the legs are similar 

 to those found upon the lips; they are covered by a thick, dry 

 crust which when removed exposes a granulating surface 

 covered with pus. 



(b) Venereal Form. In this form the external genital 

 organs of both males and females are involved. It may be 

 associated with the lip-and-leg form, but not infrequently 

 occurs independently. In males the skin of the sheath, espe- 

 cially at its orifice, is inflamed. The first symptom is the ap- 

 pearance of one or more light yellow-colored centres, necrotic 

 areas, which appear at the junction of the skin and mucous 

 membrane of the prepuce. Soon there develops an ulcer 

 which usually extends outwardly over the skin rather than 

 inwardly over the mucous membrane. By coalescence the 

 whole swollen sheath may be covered with ulcers. Occasion- 

 ally the pendant portion of the prepuce may slough. In 

 wethers the penis is rarely, if ever, attacked. In bucks, how- 

 ever, the necrosis attacks the penis, which swells ("big 

 pizzle"), becomes ulcerous on its surface, and occasionally 

 gangrenous, the distal portion of the organ not unrarely 

 sloughing off. 



In ewes the ulcerations occur in t the skin and mucous 

 membrane of the vulva, the ventral surface of the tail, and 

 the perineal region. Occasionally the vagina may be involved, 

 leading to a discharge. 



(c) Foot-rot Form. — The foot-rot form involves at first the 

 interdigital spaces, the erosions usually making their first 

 appearance at the heel. The inflammation invades the hoof 

 matrix, leading to the discharge of a thin ichor which has a 

 very characteristic pungent, penetrating odor. The foot-rot 

 form may attack any sheep in the herd irrespective of age or 

 sex. 



(d) Sore-mouth Form. — This form is seen in lambs during 

 the fall of the year. The symptoms are similar to those of 

 the lip form in older sheep. The lips of the lambs swell, 



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