144 CHAPTER 17. 



very gentle trot for a few minutes will sometimes also be needed to cause 

 the medicine to operate. With a similar view an enema may be given. 



Six or seven evacuations are quite sufficient, though grooms generally 

 like to see a dozen. 



So far as the action of the purgative is concerned, a horse moderately 

 purged may generally be put to work in about three days after the physic 

 has ceased to operate, or " set " as it is technically termed. 



A dose of physic is very apt to carry off a weakly patient from over- 

 effect ; but in some cases of fever attended with great debility it may 

 remain inoperative from want of tone in the system. Balls, which have 

 been given several days previous, are sometimes found whole in the intes- 

 tines after death. 



Some purgatives do not act directly on the intestines, but produce their 

 effects indirectly by exciting organs in connection with them, such as the 

 liver and glandular structures. 



The administration of purgatives is always attended with some danger, 

 and therefore it is desirable to use the smallest quantity which will pro- 

 cure the required effect. 



284. Horses difficult to affect with purgative medicine. 



If it be found difficult to move the bowels of any particular horse with 

 medicine, it is a good plan, in addition to the usual preparation, to put 

 him on linseed meal and bran mashes for a further twenty-four hours 

 before the administration of the dose. If in the end the physic does not 

 act, the stinting of the food will probably have done nearly as much 

 good as the medicine would have done. It is a dangerous mistake to give 

 a second dose of aloes at an interval of less than ten days, or to suppose 

 that the medicine will do harm by remaining in the system, if it does not 

 pass off visibly. Its effect is in reality simply negative. In many cases, 

 however, the medicine is passed off by the kidneys. 



285. Super-purgation. 



If the purging continues over long, and wheaten flour mixed with the 

 water fails to stop it, some rice-water gruel, made rather thick, may be 

 given frequently and in small quantities at a time, and also hay and a 

 little bruised corn mixed with dry bran. The patient should be kept 

 very quiet and warm. His legs should be wrapped in flannel bandages, 

 and his body, especially the belly, kept warm with clothing. Astringent 

 and nutritive enemata are often recommended in such cases, but their 

 utility is very doubtful. 



286. Purgatives not to be given to a weaJc horse. 



Purgatives rapidly reduce the strength partly by causing the food to 

 pass more quickly through the intestines and thereby giving less time 

 for the absorption of its nutritious parts, partly by the increased secre- 



