ANIMAL PARASITES AND PARASITIC DISEASES 



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inhabiting organs of the digestive, respiratory, and circulatory- 

 systems. Some are so minute as to be almost invisible to the 

 naked eye, while others attain a length of 12 inches or more 

 when fully developed. They cause damage by interfering with 

 the functions of the infested organs. The effects are unthrif tiness, 

 emaciation, diarrhea, anemia, and even death. 



The large white worm (Ascaris megalocephala) is frequently 

 seen in the feces of the horse. The male of this variety measures 



Fig. 80. — Large round worms in a portion of the small intestine of a hog. 



from 6 to 10 inches long, while the female may exceed 14 inches 

 in length. They produce digestive disturbances, and may even 

 mechanically clog the intestines if present in large numbers. 

 A diagnosis is made by finding one of the adults or its eggs. 

 A successful remedy to rid horses of Ascaris is 15 grams of 

 tartar emetic dissolved in 15 quarts of water. The dose should 



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