330 



THE DOMESTIC SHEEP. 



they enter the gall bladder and its connected ducts, where they 

 create such a serious functional disturbance as to cause an over- 

 flow of the bile into the blood, by which parts of the body 

 the eyes, skin and fat become yellow, and a yellow serum col- 

 lects in the abdomen, causing the diseased sheep to appear "pot- 



Fio. 14. 

 A Sporocyst. 



PIG. 15. 

 A Mature and Dividing Sporocyst. 



bellied." At first the sheep appear to thrive better than 

 usual and rapidly make fat, which, however, is yellowish in color. 

 Very soon 'the characteristic dropsy appears, a bag of fluid forms 

 'under the jaws, severe diarrhea occurs, and the animal soon 

 becomes emaciated and perishes miserably by a slow wasting until 

 completely exhausted. 



As the fluke does not inhabit salt water, salt marshes are safe 

 pasture grounds; but it does not follow that salt given to the 

 sheep is any sort of preventive or remedy. In fact, cure of the 



FIG. 17. Young and Mature Redia. 



disease is very rare, and only by the aid of accidental causes, so 

 that this disease, is a true pestilence, killing nearly every sh.eep 

 attacked, and it is only by due means of prevention that it is 

 possible to avoid it. These are the drainage of wet pastures, the 

 use of pure water from wells, and to put imported sheep through 

 a sufficient course of quarantine; carefully burning all the manure 

 made by them so as to destroy any possible source of infesting the 

 land. 



