130 Diseases of the Genital Organs 



stages, the duration is to be determined by the volume of 

 the palpable part or parts of the fetus, the volume of the 

 uterine arteries, and to some extent by the volume of the 

 uterine seal, the dilation of the cervical canal, the enlarge- 

 ment of the udder, and the sinking of the pelvic ligaments. 

 In a heifer of medium size, pregnant thirty days, the gravid 

 horn is about one to one and one-quarter inches in diame- 

 ter. When forty-five days pregnant, the gravid horn has 

 increased to one and one-quarter or one and one-half inches. 

 At sixty days, it has reached about one and three-quarters 

 inches ; at ninety days, two to two and one-half inches ; at 

 one hundred to one hundred and twenty days, three to three 

 and one-half inches. At one hundred and fifty days, the 

 gravid horn is four and one-half to six inches, and at one 

 hundred eighty days, seven to eight inches. In the cow, 

 during the first sixty days, the uterus is somewhat larger 

 than in the heifer, and later is not quite as tense as in the 

 latter, but there is no recognizable difference in size. 



At about one hundred fifty to one hundred eighty days, 

 the fetus is generally palpable. Frequently it is palpable at 

 a much earlier date even when only six to eight inches long, 

 but recognition of the fetus at this time is not at all certain 

 in any given case. Even when the fetus is recognized at 

 this early date, it is of little or no advantage, as a means for 

 determining the stage of pregnancy, over the transverse di- 

 ameter of the gravid horn. 



Once the fetus is palpable, its age is to be judged by the 

 volume of the extremity palpated. The length of the fetus 

 cannot be determined. The parts usually palpated are the 

 head or the anterior feet when in the anterior presentation, 

 or buttocks when in posterior presentation. The size of 

 these will vary with the size and age of the pregnant animal 

 and with breed. The Holstein fetus is the largest commonly 

 encountered and has large head and feet. The Jersey pre- 

 sents the other extreme. The examiner is to bear in mind 

 individual variations in size of fetuses also. The determina- 

 tion of the stage of pregnancy by physical examination is 

 evidently only approximation but, with the breeding history, 



