324 PRINCIPLES OF VETERINARY SCIENCE 



be repeated after fourteen days regardless of the number of worms 

 removed. Keep the horse from drinking until he is thirsty, 

 then set the bucket of tartar emetic solution before him and 

 allow no other water until it is all drunk. 



The large round worm (Ascaris suis) is harbored in the in- 

 testines of swine (Fig. 80). The best anthelmintic for ascarids in 

 swine is oil of chenopodium. Most satisfactory results follow 

 if the oil is given alone instead of mixing it with the feed. The 

 dose is 4 cubic centimeters for a 75 to 100 pound pig given in 1 

 ounce of castor oil. Each pig should be fasted for twenty-four 

 hours before being given this medicine. 



The thorn-headed worm (Echinorhynchus gigas) is also com- 

 monly found in the intestines of swine. Although not belonging 

 to the class of round worms it is described here for convenience. 

 In large numbers they cause symptoms which are frequently con- 

 fused with hog cholera. A heavily infested animal shows per- 

 sistent unthriftiness, digestive disorders, and fails to respond to 

 the hog cholera serum treatment. The mature worms are white 

 and measure from 8 to 10 inches long. They are usually found 

 .with the head firmly imbedded in the wall of the hog's intestine. 

 Not infrequently the head has perforated the bowel rendering it 

 unfit for sausage casings. Their life history is very interesting as 

 a secondary host is required. Hogs become infected through 

 eating the large June bug, or its grub, which contains the larvae 

 of the worm. The beetle or grub thus plays the part of an 

 intermediate host. 



The lung worm of sheep (Strongylus) is a very small, thread- 

 like worm which produces verminous bronchitis. It will serve 

 as an example of this class of worms. Various names have 

 been given to the disease produced by lung worms, viz., hoose, 

 husk, and paper skin or lamb disease. The worms are also found 

 thriving in the bronchial tubes and lungs of pigs and calves. 

 Among the symptoms which result are : a cough which comes on 

 in spasms, loss of appetite, a dry and harsh skin, accelerated 

 breathing, anemia, and bronchitis and pneumonia. During 

 favorable seasons an entire flock of sheep may become diseased 

 and large numbers die. Death is usually directly due to suffo- 

 cation by plugging the air passages. Treatment is not satis- 

 factory. However, a mixture containing equal parts of turpentine, 

 chloroform, and olive oil injected into the trachea has been used. 



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