70 DISEASES OF SHEEP. 



of the belly are very seldom afflicted with itch, and then 

 only in a very advanced stage pi the disease. The itch 

 always begins upon a small spot, and extends from time to 

 time until the entire surface of the body is affected and the 

 wool removed therefrom ; such a general spreading of the 

 disease advances very slowly, and often requires from four 

 to eight months. In hot stables and during summer-time 

 the disease spreads in a short time ; in cold weather the 

 progress is very slow. Although the disease in itself is not 

 of a dangerous nature, death will surely result from its 

 long continuance. The animal grows lean, notwithstand- 

 ing a good appetite ; the skin is entirely deprived of wool, 

 covered with a discolored, nauseous and suppurated mois- 

 ture and overloaded with a thick scab. Dropsy, pulmo- 

 nary disease, lingering fever, etc., ensue, which finally re- 

 sult in death ; when the animal has been well fed during 

 the disease, the last-mentioned consequences may take place 

 after one or two years. 



There are two causes of this disease : it may originate in 

 itself or from infection. The first cause is said to be a con- 

 sequence of constant exposure to wet or rain, especially in 

 summer, of want of good feeding, and of different morbid 

 conditions of the animal. In most cases, however, infection 

 forms the first cause of the disease. When the diseased 

 skin of a scabby animal is examined, either with the naked 

 eye or by means of a magnifying glass, numerous small in- 

 sects, the so-called scab-mites (very similar to the scab- 

 mites of the horse) may be detected. The transfer of each 

 mite from scabby to healthy sheep forms the only and ex- 

 clusive cause of infection, after which the disease is regu- 

 larly formed in a period of from ten to sixteen days, there 

 being no indication of infection before the seventh day ; on 

 the seventh or eighth day the mite itself may be detected 

 upon the skin of the infected animal ; from the ninth to 



