PARASITES AXD PARASITIC DISEASES OF HORSES 



25 



important preventive measure, as is shown elsewhere in this circular. 

 Little can be accomplished in the way of pasture sanitation except on 

 farms where thoroughbred or other valuable horses are raised. On 

 these farms the removal of manure deposits from pastures may be 

 practiced, as this procedure will remove almost all the parasite mate- 

 rial before it can develop and spread. Such a procedure is necessarily 

 troublesome and expensive and can be undertaken only by breeders to 

 whom the question of expense is of secondary importance. The 

 average breeder will have to resort to simpler and less radical 

 measures, such as avoiding the overstocking of pastures, frequent 

 rotation of pastures, and special attention to foals. Where over- 

 stocking and the use of wet pastures are unavoidable, and rotation 

 is impossible, reliance must 

 be placed on treatment as 

 often as necessary for 

 control. 



Horse breeders, and even 

 the general farmer, should 

 pay considerable attention to 

 the sanitation of paddocks in 

 which the newly born foals 

 are kept. The foals should 

 be kept there for several 

 weeks before they are put on 

 pastur e. The removal of 

 manure from the paddocks, 

 at least once a week, will 

 cut down the supply of eggs 

 and larvae to which the 

 foals would otherwise be ex- 

 posed. This precaution will 

 help to tide the foals over the 

 most critical period of their 

 lives. 



Young animals of all sorts are special cases and require special 

 care. In the last analysis the saving of young livestock involves the 

 same precautions which are used in connection with the prevention of 

 sickness in children. Above everything else, a wholesome food 

 supply and clean surroundings 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 stron- 

 glyes, which are much smaller in most cases than blood strongyles,. 

 though some are almost as large. (Fig. 18.) These worms occur 

 in the colon and cecum and some of them produce visible injuries. 

 One species, Triodontophoi^us temdcollis, 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 stron- 

 gyles, the many species known as cylicostomes, species of Trichonema. 

 15390°— 30 i 



Figube 18. — Small strongyles of the horse. 

 The larger forms are Poteriostomum species 

 and the smaller ones are cylicostomes. 

 Natural size 



