Common Parasites 33 



will kill the larvae. Oil of tar also will kill the larvae and prevent 

 fresh infestation. 



Xote. There are several other species of flies which infest wounds 

 of sheep and other farm animals in a similar manner. It is not 

 considered necessary to discuss all of them as the same treatment 

 applies in each species. 



INTERNAL, PARASITES 



Lung Worms (Strongylus filaria), (Verminous bronchitis). 



These worms infest the air passages of sheep and goats. They 

 are thread-like, white and two to four inches in length. In mature 

 sheep little effect of their presence is noted but in lambs and year- 

 lings severe losses are sometimes caused. 



The presence of the parasites in the air passages produces irrita- 

 tion resulting in the establishment of chronic couglji and loss of con- 

 dition, and reduction of vitality. Pneumonia and death sometimes 

 result from the infestation. 



Life History. The female worms produce eggs which are coughed 

 out and contaminate feed and water supplies. Low lands not well 

 drained appear to favor the propagation of the parasites. It is 

 believed that the worms are hatched on the ground and taken into 

 the stomach with food or water later migrating through the tissues 

 to their favorite location in the lungs. 



Symptoms. In lambs and yearlings severe attacks of coughing, 

 difficult breathing, anemia, (paleness of the skin and mucous mem- 

 branes), dryness of the skin, loss of strength and rapid loss of 

 flesh are the most notable signs of infestation. When the para- 

 sites are present in large numbers in the intestines, indigestion and 

 attacks of colic with intense thirst result. The live parasites may 

 be found in the discharges from the nostrils and in the manure. 



Treatment. Preventive treatment consists in providing well 

 drained pastures, especially for lambs and yearlings, and pasture 

 rotation. Access to salt at all times is essential. 



Various treatments are recommended for the destruction of the 

 parasites in the air passages but these are of doubtful value. They 

 consist of fumigation with burning sulphur, the injection of ben- 

 zine, turpentine or other worm destroyers into the wind pipe. In- 

 fested animals should receive the best of care and careful and lib- 

 eral feeding. The carcasses of all animals dying on the farm should 

 be burned, or deeply buried, in order to prevent the spread of para- 

 sites and diseases. 



Intestinal Worms (Oesophagostoma columbianum), (Nodular dis- 

 ease). 



These worms are thread-like, three-fourths to one inch in length 

 and are found in nodules in the wall of the intestines of sheep, 



