Atony of the Genital Tract, etc. 261 



On the whole, therefore, we consider that the manual or 

 mechanical dilation of the cervix uteri should be strictly limited 

 to those cases where the sterility is traceable to a definite ob- 

 struction in the canal, which it is possible to overcome by the 

 operation. 



Hypertrophy of the Os Uteri.— Aside from the closure of 

 the OS uteri, Zschokke, Hess and others have observed hyper- 

 trophy of the cervix as a hindrance to impregnation. In these 

 cases, the os uteri externum projects far into the vagina, and is 

 enlarged and firm. Zschokke has found this condition only in 

 old cows which had repeatedly given birth. Hess believes that 

 this condition may be transmitted to the offspring. The condi- 

 tion consists chiefly of a hypertrophy of the mucous membrane 

 and the folds may reach ten times their normal size. Some 

 veterinarians have recorded tuberculosis of the cervix uteri. 

 Zschokke alludes also to the formation, about the os uteri externum 

 'in cows, of mucous membrane flaps as much as 6 cm. long, which, 

 in his judgment, might act as a hindrance to the migration of 

 spermatozoa through the cervical canal. In the mare this con- 

 dition is very common in conjunction with general atonic condi- 

 tions of the genital tract, which we consider below, where we 

 shall deal with the problem of handling. The general handling 

 of hypertrophy of the os uteri, or vaginal portion of the cervix 

 uteri, must usually be coupled with an unfavorable prognosis. 

 If the condition is static, if noactivedisea.se processes are present, 

 and it is believed that parturition could be safely accomplished, 

 artificial insemination may be successfully applied, if a small- 

 caliber syringe nozzle can be introduced through the hypertrophied 

 organ. If active disease processes are present, appropriate 

 remedies should be applied for their cure. In general, however, 

 the condition is beyond remedy. 



7. Atony of the Genital Tract and Dilation of the 



Cervix Uteri. 



In contrast to constriction or occlusion of the os uteri externum, 

 -we more commonly meet in the mare with an abnormal dilation 

 of the passage. The os uteri is unusually wide open and flaccid 

 and readily admits of the entrance of several fingers or of the 

 entire hand. 



