DISEASES OF CATTLE 165 



mode is to press the closed fist strongly inward in the same situa- 

 tion and hold it so, forming a deep indentation in the abdominal 

 wall. Presently the knuckles are felt to be struck by a solid body, 

 which is no other than the fetus that had been displaced to the left 

 by the push of the hand, and now floats back in its liquid covering 

 (amniotic fluid) downward and to the right. 



Of all the modes of examination by touch, that done through 

 the rectum gives the earliest satisfactory indications. The hand 

 and arm well oiled are introduced, and the excrement having been 

 removed if necessary, the palm of the hand is turned downward 

 and the floor of the pelvis carefully examined. There will be felt 

 in the median line the pear-shaped outline of the bladder, more or 

 less full, rounded or tense, according to the quantity of urine it con- 

 tains. Between this and the hand will be felt a soft, somewhat 

 rounded tubular body, which divides in front into two smaller 

 tubes or branches, extending to the right and left into the abdomen. 

 This is the womb, which in its virgin, or unimpregnated, condition 

 is of nearly uniform size from 'before backward, the main part or 

 body being from 1^2 to 2 inches across, and the two anterior 

 branches or horns being individually little over an inch wide. Im- 

 mediately after conception the body and one of the horns begin 

 to enlarge, the vacant horn remaining disproportionately small, 

 and the enlargement will be most marked at one point, where a 

 solid rounded mass indicates the presence of the growing embryo. 

 In case of twins, both horns are enlarged. At a more advanced 

 stage, when the embryo begins to assume the form of the future 

 animal, the rounded form gives place to a more or less irregular 

 nodular mass, while later still the head, limbs, and body of the 

 fetus may be distinctly made out. The chief source of fallacy is 

 found in the very pendent abdomen of certain cows, into which in 

 advanced gestation the fetus has dropped so low that it can not be 

 felt by the hand in the rectum. . The absence of the distinct outline 

 of the vacant womb, however, and the clear indications obtained 

 on external examination through the right flank will serve to pre- 

 vent any mistake. The fetus may still be felt through the rectum 

 if the abdomen is raised by a sheet passed from side to side 

 beneath it. 



Still another sign is the beating of the fetal heart, which may 

 be heard in the latter half of pregnancy when the ear is pressed on 

 the flank in front of the right stifle, or from that downward to the 

 udder. The beats, which are best heard in the absence of rumbling 

 are about 120 per minute, and easily distinguished from any bowel 

 sounds by their perfect regularity. 



DURATION OF PREGNANCY. 



From extended statistics it is found that the average duration 

 of pregnancy in the cow is two hundred and eighty-five days. A 

 calf born at the two hundred and fortieth day may live, and a case 

 is reported by Dietrichs of a calf born on the three hundred and 

 thirty-fifth day, and another by the American Journal of Medical 

 Science as born on the three hundred and thirty-sixth day. It is 



