148 DISEASES OF THE LIVER 



Symptoms. — In cattle, as a rule, notwithstanding the 

 great inroads which the parasites make on the liver, clinical 

 symptoms are absent. In sheep, however, they produce 

 symptoms of a severe general disease — anemia, hydremia, 

 and ultimately cachexia. After a latent period of one or 

 two months, and usually in the autumn, the infested sheep 

 begin showing symptoms of general anemia ("paper skin"). 

 In the early winter the sheep begin to get thin, show chronic 

 indigestion, weakness, edema of the eyelids, throat region, 

 and ventral portion of the abdomen (anasarca), and also 

 ascites. As these symptoms may also occur in other worm 

 plagues of the sheep a diagnosis can be made only by a 

 necropsy or by examining the feces for eggs. 



Course. — The course is very varied. In severe cases after 

 a period of three months death ensues. In other instances 

 the sheep may live through the winter and die in the spring, 

 or recover after the emigration of the flukes, which takes 

 place in the following autumn. 



Treatment. — A medicinal treatment is of no value. Experi- 

 ence with arsenic and the various vermifuges have given no 

 results. The principal indication is to strengthen the con- 

 stitution of the sheep by intensive feeding and proper care. 



Prophylaxis. — The sheep should be kept off infested 

 pastures, especially land which lies low. The sheep should 

 be given a wide range and kept in small flocks. Short 

 pasture is dangerous because the cercarise are found close 

 to the grass roots. The egg-infested manure should be 

 spread out on land which is to be tilled and the livers of the 

 dead sheep rendered harmless. 



ECHINOCOCCUS DISEASE OF THE LIVER. 



Definition. — An inflammation of the liver due to an invasion 

 of the echinococcus parasite. 



Occurrence. — The disease is quite common in cattle and 

 swine but rare in other animals. 



Natural History. — The echinococcus cyst is the larva of the 

 Taenia echinococcus, a tapeworm of the dog. The segments 

 of the tapeworm are voided with the feces of the dog, pollut- 



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