Gastric and Intestinal Bots. 77 



When the larvae are attached to the rectum or anus there is the 

 stiff, straddling gait, the switching, spasmodic depression and 

 rubbing of the tail, and sometimes the presence of the larva at- 

 tached to the anal ring. 



Treatment. Prevention should be aimed at. Stable the ani- 

 mals in summer and fall ; clip ofE the long hairs from lips, nose, 

 jaws, shoulders and legs, so that the flies may fail to find the cus- 

 tomary supports for their eggs ; groom thoroughly so as to de- 

 tach the eggs by brush or damp sponge before they have had time 

 to hatch out their embryo ; smear frequently with oil the parts 

 where the eggs are usually deposited to prevent their cement from 

 adhering ; cover with a cloth under the jaws to keep the flies at a 

 ■distance ; crush any larvae that may be seen in or beneath the balls 

 of manure in summer or autumn. 



Therapeutic treatment is unsatisfactory owing to the extraordi- 

 nary vitality of the larvae. They will live almost indefinitely in 

 a saturated solution of common salt, in alcohol, in castor oil, in 

 olive oil, in a strong solution of aloes, sodic sulphate, ar.senic or 

 asafoetida, in extract of nux vomica, in solutions of morphia, 

 narcotine, strj'chnia, cupric sulphate or tobacco. Ivime water and 

 empyreumatic oils failed to kill them. Numan tried in vain to 

 kill them with irrespirable gases, hydrosulphuric, hydrochloric, 

 and prussic acids, and caustic ammonia. Voigtlander found that 

 they survived fifteen hours in a concentrated solution of potash. 

 The pulped roots of bryony, acorns and sulphate of mercury have 

 been strongly recommended, but failed in general application. 



Magne strongly recommends oil of turpentine as killing the 

 bots, even when largely diluted in milk. Santy says they are 

 promptly killed by pure bile, but it is useless if diluted. Gayot 

 recommends ether and empyreumatic oils in a mucilaginous solu- 

 tion. Rey recommends benzine as the best resort in one or two 

 ■ounce doses. More recently carbolic acid in half ounce doses 

 largely diluted has been found effective. Bisulphide of carbon 

 bas also proved useful. It may be given in doses of i drachm in 

 alcohol, or in bolus with aloes. 



AH active agents are likely to be more effective in the young 



soft bot in fall. Percher says the berries of the azedarach planted 



around stables are used in the South to protect horses against bots. 



Apart from medicinal agents a nourishing diet which will sus- 



