IMPREGNATION 263 



been said, subside, and are not again noticed until after parturition; they 

 reappear, however, very soon after that act has taken place, and it is be- 

 lieved that on the ninth day subsequent to foaling, the mare will be more 

 successfully impregnated than at any other time. 



With some mares impregnation does not take place readily, and this 

 fault may be due to various causes, such as the animal being too old when 

 tried for the first time, too fat or debilitated, &c., in which cases medi- 

 cines which stimulate the generative functions, such as cantharides in very 

 small doses, tonics, or stimulating food, may be of service. For other cases 

 in which the cause is located in the organs of generation, the remedy to 

 be resorted to will depend upon the character of the obstacle. The most 

 frequent of the causes which hinder or prevent impregnation and produce 

 sterility appears to be one of a mechanical kind closure of the small 

 opening (os) in the neck (cervix) of the uterus, leading to the interior 

 of that important receptacle. This can only be ascertained by a manual 

 examination, which discovers the opening into the uterus to be impervious, 

 through contraction or alteration in structure of the neck of that organ. 

 For very many of those cases the canal can be dilated by the fingers im- 

 mediately before the mare is brought to the stallion ; and great success has 

 attended the employment of the india-rubber impregnation-tube, which is in- 

 serted into the canal before service, and withdrawn when that has been effected. 



When impregnation has been successfully accomplished, certain changes 

 are usually observed in the behaviour of the mare which lead to the sup- 

 position that such is the case. Perhaps the most notable indication is the 

 disappearance of "sestrum" or "heat". It is ordinarily the practice to 

 present a mare to the stallion nine days after she has foaled, this being the 

 time at which, as has been already stated, conception is popularly believed 

 to take place with most certainty. About a fortnight afterwards she is 

 again presented, and generally in another fortnight a last trial is made, 

 when if the animal refuses intercourse it is concluded that she is pregnant, 

 especially if no unfavourable signs have been observed in the interval, such 

 as a desire for the male. 



In a short time, also, the majority of mares, if they have been irritable 

 and restless previously, become quieter and more docile, if not absolutely 

 torpid, and inclined to become fatter. Seldom is anything more noticed 

 until pregnancy has advanced to the sixth or seventh month; so that 

 though the question is often asked the expert as to whether a mare is in 

 foal before that period, a reply in the affirmative is rather hazardous, and 

 can only be based on the indications just alluded to, unless recourse be 

 had to a manual examination per rectum or through the genital passage, a 

 procedure which is not advisable in all cases. 



