102 The Practical Stud Groom. 



to facilitate the passage of the sperm cell of the stallion into 

 the uterus of the mare on its way to meet the germ cell or 

 ovum descending via the fallopian tubes. Broadly speak- 

 ing, the period of oestrum lasts about seven days. Again, 

 speaking generally, it will be found that for the first two 

 days there is little or no change as regards dilation of the 

 os; the next three days there is full dilation, followed during 

 the final two days by a rapidly increasing contraction. 



The author's practice, when examination by aid of the 

 speculum reveals rigidity of the os to be present, is to post- 

 pone service for that day, and to examine the mare morning 

 and afternoon each succeeding day till the os is found fully 

 relaxed and dilated. It is somewhat difficult to give a satis- 

 factory pen picture of the contrast between the two condi- 

 tions. I can think of no more apt illustration than this : 

 The tight, hard rosebud represents the rigid os, the full- 

 blown rose just past its prime the relaxed. The full-blown 

 rose stage, concurrent with a clean normal-coloured mucous 

 membrane, is the physiological moment for service to take 

 place, when the chances of conception are 99 per cent. A 

 mare may be covered four days in succession during the 

 " heat," yet if a foal results it is the fruit of one only of 

 these services ; the other three represent so much squandered 

 vitality on the stallion's part. The practice of some stud 

 grooms is to have the mare covered the first day she comes 

 kindly into " use," then miss a day, cover again the follow- 

 ing day, miss the next day, and then the following day, if 

 the mare is still kindly in " season," to give her a third and 

 final service. I readily admit that under this system the 

 resulting foal crop is generally satisfactory as regards 

 numbers, but what of the quality? If stallion No. 1 covers 

 twe 1 ve mares three times each, and stallion No. 2 covers 

 twelve once each, and twenty-four foals result, will it be 



