666 DISEASES OF SWINE 



out the bowels and carry out the parasites. For this purpose 

 castor oil is an excellent agent, and may be stirred up with the 

 milk along with the turpentine. By giving the treatment on an 

 empty stomach the bowels are free from a large 'mass of undigested 

 food, and the turpentine has a good chance to get at and destroy 

 the parasites. 



THE PIN-WORM ((ESOPHAGOSTOMA DENTATUM) 



In the hog of the United States the pin-worm is a fairly common 

 parasite. In scientific text-books this worm is described under the 

 name of OEsophagostoma dentatum, that being its correct official 

 or scientific name. To the farmer and stockman it is much better 

 known under the name of pin- worm. This parasite is a very small 

 worm, and is found mostly in the large bowel. A few may be 

 found in the small intestine, but the greater number occur in the 

 cecum and colon of the large intestine. 



Description. — The pin-worm is a very small parasite. The male 

 is only about J to J inch long and the female i to | inch. The 

 body is very small in caliber and white or grayish-white in color. 

 The worm is pointed at both ends, and this is especially marked in 

 the female parasite. 



S3miptoms. — If only a few of the parasites are present no well- 

 marked symptoms are produced. The location of the worms in the 

 large bowel and their small size makes it possible for even consider- 

 able numbers to be present without the production of any severe 

 symptoms. When large numbers are present they produce diar- 

 rhea, loss of appetite, improper nourishment, poor quality of the 

 blood, and an unthrifty appearance. In severe cases, if left un- 

 treated, the parasite may produce death. This is especially hkely 

 to happen if, in addition to pin-worms, the round-worm or thorn- 

 headed worm be also present. A positive diagnosis of pin-worms is 

 made by finding of the worms or the eggs of the parasite in the feces. 

 Often in an animal that has died, when the carcass is opened up and 

 the large bowel cut into, the contents will be found to be fairly 

 wriggling with pin-worms, which are present by the thousands. 



Mode of Infestation. — The mode of infestation with the pin- 

 worm is just a])out the same as in the case of the round-worm. The 

 eggs of the female are carried out with the feces and are mixed with 



