320 HORSE, SWINE AND POULTRY DISEASES 



proportion of the subjects perished. By operating through the ya- 

 gina the risk can be largely obviated, as the danger of unhealthy in- 

 flammation in the wound is greatly lessened. The animal should be 

 fixed in a trevis, with each foot fixed to a post and a sling placed 

 under the body, or it may be thrown and put under chloroform. The 

 manual operation demano!s special professional knowledge and skill, 

 but it consists essentially in making an opening through the roof of 

 the vagina just above the neck of the womb, then following with the 

 hand each horn of the womb until the ovary on that side is reached 

 and grasped between the lips of forceps and twisted off. It might be 

 torn off by an ecraseur especially constructed for the purpose. The 

 straining that follows the operation may be checked by ounce doses 

 of laudanum, and any risk of protrusion of the bowels may be ob- 

 viated by applying the truss advised to prevent eversion of the womb. 

 To further prevent the pressure of the abdominal contents against 

 the vaginal wound the mare should be tied short and high for twenty- 

 four or forty-eight hours, after which I have found it best to remove 

 the truss and allow the privilege of lying down. Another important 

 point is to give bran mashes and other laxative diet only, and in 

 moderate quantity, for a fortnight, and to unload the rectum by 

 copious injections of warm water in case it should threaten to become 

 impacted. 



STERILITY. 



Sterility may be in the male or in the female. If due to the 

 stallion, then all the mares put to him remain barren ; if due to the 

 mare, she alone fails to conceive. 



INDICATIONS OP PREGNANCY. 



As the mere fact of service by the stallion does not insure preg- 

 nancy, it is important that the result should be determined, to save 

 the mare from unnecessary and dangerous work or medication when 

 actually in foal and to obviate wasteful and needless precautions 

 when she is not. 



The cessation and nonrecurrence of the symptoms of heat (hors- 

 ing) are most significant though not an infallible sign of conception. 

 If the sexual excitement speedily subsides and the mare persistently 

 refuses the stallion for a month, she is probably pregnant. In very 

 exceptional cases a mare will accept a second or third service after 

 weeks or months, though pregnant, and some mares will refuse the 

 horse persistently, though conception has not taken place, and this 

 in spite of warm weather, good condition of the mare, and liberal 

 feeding. The recurrence of heat in the pregnant mare is most likely 

 to take place in hot weather. If heat merely persists an undue length 

 of time after service, or if it reappears shortly after, in warm weather 

 and in a comparatively idle mare, on good feeding, it is less signifi- 

 cant, while the persistent absence of heat under such conditions may 

 be usually accepted as proof of conception. 



An unwonted gentleness and docility on the part of a previously 

 irritable or vicious mare, and supervening on service, is an excellent 

 indication of pregnancy, the generative instinct which caused the 

 excitement having been satisfied. An increase of fat, with softness 



