16 



CIRCULAR 148, TJ. S. DEPARTMENT OP AGRICULTURE 



from 6 to 12 fluid drams (25 to 50 cc) for a 1,000-pound animal. 

 This drug usually need not be accompanied with a purgative, but 

 it is advisable to give a saline purgative immediately following the 

 administration of carbon tetrachloride for the removal of worms, 

 particularly ascarids, from colts. 



Prevention. — Prevention of ascarid infestation requires special 

 care of foals and young horses. The time to begin is before the foal 

 is born. The foaling barn should be of sanitary construction and 

 should be cleaned and washed with hot water and lye before the 

 pregnant mare is placed in it. The mare and foal should be kept 

 in a clean paddock adjoining the barn. It is best to use a paddock 

 from which other horses have been absent for at least a year. The 



stable and paddock 

 in which the mare 

 and foal are kept 

 should be cleaned 

 daily if possible, lit- 

 ter and manure be- 

 ing removed. 



These precautions 

 are designed to pre- 

 vent the foals from 

 becoming heavily 

 infested with asca- 

 rids at an early age, 

 and before they have 

 developed the neces- 

 sary reserve vitality 

 to cope successfully 

 with a heavy worm 

 infestation. When 

 the foal is moved to 

 a pasture it is essen- 

 tial to select one 

 which is clean and 

 that has not been 

 used by horses for a 

 year or longer. 

 Horses may be 

 moved to cow and 

 sheep pastures and 

 vice versa, because parasites of ruminants are not transmissible to 

 horses, and equine parasites are not transmissible to cattle and 

 sheep, as a rule. Proper disposal of manure and sanitary meas- 

 ures recommended in connection with the control of blood strongyles 

 Avill also help to prevent infestation with ascarids. 



While infestations with ascarids can be acquired on pastures, 

 and often are so acquired, it is important to remember that ill-kept 

 stables, in which manure is allowed to accumulate (fig. 9), are also 

 the sources of heavy infestations with intestinal roundworms, pin- 

 Avorms, and other threadworms. Under pasture conditions many 

 eggs and larvae succumb to drought and to other unfavorable in- 

 fluences which prevail in the open. In manure-laden stalls parasite 



Figure 9. 



-Type of insanitary box stall. Note accumu- 

 lation of litter "and manure. 



