2S 



CIRCULAR 14S. U. S. DEPARTMENT OF AGRICULTURE 



the foals would otherwise be exposed. This precaution will help to 

 tide the foals over the most critical period of their lives. 



Young animals require special care much the same as children. 

 Above everything else, a wholesome food supply and clean surround- 

 ings are the best safeguards against disease. Special precautions to 

 prevent foals from becoming parasitized are essential parts of sound 

 management in horse-breeding establishments and on the average farm. 



THE SMALL STRONGYLES 



In addition to the blood strongyles or palisade worms, horses are 

 commonly infested with numerous closely related species of strongyles. 

 which are much smaller in most cases than blood strongyles. though 



Figure 19. — Lesions produced by one of the smaller horse strongyles: A, enlarged 

 view of lesion with worms, Triodontophorus temiicollis, surrounding it; B, types 

 of lesions. (From Ransom and Hadwen, 1918.) 



some are almost as large (fig. 18). These worms occur in the colon and 

 cecum and some of them produce visible injuries. One species. Tri- 

 odontophorus tenuicottis, produces rather severe ulcers in the wall of 

 the colon (fig. 19). probably by means of the sharp teeth in their 

 mouth cups. Some of the smaller horse strongyles. the many species 

 known as cylicostomes. species of Trichonema or Cylicostomum. are 

 usually about a half inch or less in length and grayish white in color, 

 and occur attached to the gut wall or free in the contents of the large 

 intestine of the horse. These worms do not feed on blood, at least 

 ordinarily, but they may feed on the mucosa of the large intestine. 

 The immature forms of some cylicostomes occur in nodules in the 

 wall of the large intestine. 



The small strongyles of the horse contribute to the picture of gross 

 parasitism, and together with the large strongyles. are responsible for 



