XLY. 

 CONTAGIOUS DISEASES OF SHEEP. 



VARIOLA OVINAE (Sheep-Pox) 



Is a contagious and infectious eruptive disease, analogous to 

 small-pox and cow-pox. This disease lias caused great loss to 

 slieep-owners in Britain as well as in other countries. It occurs 

 in two forms, malignant and benign. The malignant form never 

 produces vesicles; the sheep lose their eyes, the wool falls out, 

 the skin cracks, and the nostrils are filled with a fetid discharge. 

 In the benign form, vesicles appear; their scabs falling off, leave 

 pits on Avhich the wool never grows again. 



Symptoms. — The period of incul)ation is about fifteen days. 

 As in all fevers, there is a rise in temperature, and in this it is 

 well marked, rising as high as 107 or lOS. Soon little papulse or 

 nodules, deeply imbedded in the dermis, having a florid red 

 aspect, make their appearance. They are first seen on the sides 

 of the anus and thighs, and on the cheeks and lips, causing the 

 skin to have a flea-bitten appearance. The papula gradually en- 

 larges in size, then becomes elevated and transparent in the cen- 

 ter. The papula is now a vesicle containing a liquid, at first 

 transparent, then turbid; ultimately it becomes dry, hardens into 

 a crust, and is cast off with the epidermis. 



The affected animals separate from their fellows; their heads 

 hang low; the breathing is quick and short; the eyelids swollen, 

 the conjunctiva reddened; a discharge of mucus from the nos- 

 trils; yellow spots appear on the pituitary membrane; the pulse 

 is quick and wiry; rumination is suspended; food is refused and 

 there is great thirst for water. The feet and ears are usually 

 cold, while the surface of the body is hot. These symptoms are 

 shown from the commencement of the eruption, and do not albate 



(477) 



