338 DR. LEGEAR'S STOCK BOOK. 



CHAPTER XXVII. 

 THE DISEASES OF SHEEP. 



SCAB, OR SCABIES. 



Scab, or scabies, is a very common disease in some countries, 

 causing serious loss to sheep owners. It is very contagious, and 

 the insects which cause the disease may remain in the pasture for 

 years and then cause the trouble. Every precaution should be 

 taken to keep the infection out of the flock. 



Causes. This disease is purely of a local nature, and due to 

 a parasite. This parasite or insect is of the class "dermato- 

 dectes," which simply hold on to and prick the skin. This para- 

 sitic insect is very small, and does to a certain extent burrow be- 

 neath the outer layer (cuticle) of the skin, but never burrows 

 very deeply. 



Symptoms. Scab is easily detected, as the symptoms are 

 very plain. The animal is very restless and uneasy, and will rub 

 and scrach itself on some object or with its hoofs until the wool 

 begins to fall off in patches. Examine the skin and it will be found 

 to be considerably reddened and inflamed, with the formation of 

 blisters which break and discharge- a watery fluid (serum). These 

 finally dry up and form sores or scabs, a characteristic sign of the 

 disease. The whole fleece may drop off, or nearly so, and leave 

 the poor animal a sight to behold. The animal loses flesh and 

 spirits, becomes weak and debilitated, etc. 



Treatment. It is not difficult to cure, if the treatment is 

 thorough and of the proper kind. It is of the utmost importance 

 to keep all animals that are free from the disease away from 



