144 Diseases of the Genital Orga?is 



canal of the female with sufficient promptness that the 

 spermatozoa shall have lost none of their vigor. In large 

 animals (horse and cow) semen may be collected immedi- 

 ately after coitus by introducing the hand into the vagina, 

 using it as a ladle to gather up and withdraw the contents, 

 and may then be placed in a wide-mouthed bottle or other 

 vessel, immersed in water at a temperature of 100° to 105° 

 F. The semen may then be diluted, if required, by adding 

 sterile physiologic salt solution of body temperature. Di- 

 luted or undiluted, the semen may be introduced into the 

 vagina, cervical canal or uterine cavity of another female 

 which it is desired to fertilize. The introduction may be 

 made with a syringe, a funnel fitted with a tube, or other 

 apparatus. 



Spermatozoa have been kept artificially in a motile state 

 for many hours. In the healthy genital tract they presuma- 

 bly retain their motility for days. Motility of the sperma- 

 tozoa is not proof of fertilizing power, and no satisfactory 

 data are at hand indicating how long after ejaculation sper- 

 matozoa retain vigorous fertility. It is probably for a few 

 hours only when in the healthy genital tract, where the 

 spermatozoa unquestionably live longer than when kept out- 

 side the body. In mares and cows, rape is occasionally in- 

 duced by the breeder, under the belief that it will cause es- 

 trum to appear soon. In other cases, the female has been in 

 estrum, which, before opportunity for coitus has occurred, 

 ceases and the owner hopes by belated coitus, under com- 

 pulsion, to secure fertilization. Rape virtually always, if 

 not always, fails of results. It is reasonable to assume that 

 artificial insemination can be no more productive of results 

 than rape. Mule breeding is based upon approximate rape, 

 but the resistance of the mare is not because she is not in 

 estrum but owing to her repulsion to coitus with the ass. 

 It appears that artificial insemination must, therefore, ap- 

 proximate the essentials of physiologic coitus. The sperma- 

 tozoa need to be transferred promptly, during estrum. The 

 suggestion that semen may be transported long distances 

 and used successfully should be discounted liberally until 



