Common Parasites 



19 



ed herbage eaten by animals carries the larvae into the stomach 

 and intestines from whence they gain access to the liver and soon 

 reach maturity in the bile ducts. 



Symptoms. Animals infested with 

 liver flukes present symptoms very sim- 

 ilar to those prescribed as occurring in 

 animals infested with stomach worms, 

 although the proportion of deaths is not 

 so great. 



Post Mortem Findings. Post mortem 

 examination discloses the presence of 

 flukes in the liver. The number may 

 be few or many. As the parasites live 

 upon the liver substance areas of in- 

 flammation and necrosis are found. In 

 the debris in cavities the flukes may be 

 found. 



Treatment. Preventative treatment 

 consists in draining all swampy areas, 

 pasture rotation and providing access to 

 salt at all times. 



Medicinal Treatment. Medicinal 

 treatment is unsatisfactory on account 



a 



FIG. 47. a, The common liver 

 fluke (Fasciola hepatica). b, of the location of the parasites m the 

 The large American fluke (Fa*- liver. Digestive tonics are indicated 

 dola niagna). Natural size. j n t he treatment of animals presenting 

 (After Bureau of Animal In- 

 dustry Bulletin 19.) 



Lung AVorms (Strongylus micrurus), (Strongylus pulmonalis). 



These are thread-like worms, one and one-half to three inches 

 long, which inhabit the air passages and sacs of the lungs. Their 

 presence causes irritation which results in bronchitis or pneumonia. 

 Bronchitis from this cause is more common in calves than in adult 

 cattle. 



Symptoms. In the beginning the symptoms are slight and it is 

 only in cases of rather severe infestation that the evidences of in- 

 festation are plain enough to make an accurate diagnosis practical. 

 These are loss of appetite and accompanying loss of condition; 

 rough coat of hair, emaciation; chronic cough, which gradually 

 becomes worse and more painful; and rapid breathing, which final- 

 ly becomes so difficult that the infested animal smothers. 



Treatment. The medicinal treatment of strongylosis is generally 

 unsatisfactory. If medicines of sufficient strength and in sufficient 

 quantity are injected into the air passages doubtless the irritation 

 produced by the medicine will be as severe as the irritation caused 

 by the parasites. Such treatment is generally useless or positively 

 harmful, although frequently recommended. The inhalation of 



