GENITAL ORGANS OF THE COW 



519 



wall is also thicker. Its average lenj>;th in the non-pregnant animal is al)Out eight 

 inches (ca. 20 cm.); but in the pregnant cow the length increases to twelve inches 

 (30 cm.) or more. The recto-genital pouch of peritoneum extends backward about 

 five inches (ca. 12 cm.) on the dorsal surface, while ventrally the serous coat only 

 extends backward about two inches (ca. 5 cm.). 



This gives ample space dorsally for the incision of the fornix vagina' in oophorectomy. 



In the ventral wall of the vagina, between the nuiscular and mucous coats, 

 there are frequently present the two canals of Gartner (Ductus epoophori longitu- 

 dinales). When well tleveloped the\' may attain the diameter of a goose quill, 

 and may be traced forward to the anterior part of the vagina or even further. 

 They open posteriorly near the external urethral orifice. 



These tubes are remnants of the Wolffian ducts, and, like other foetal vestiges, are very 

 variable. Roder states that the right canal was absent in over 52 per cent., the left in only 22 per 

 cent., of the cows examined by him. In some cases they may be traced in the broad ligaments for 

 a variable distance toward the ovary. They are of clinical interest in that cysts frequently form 

 along their course. 



Fig. 415. — Diagr.vmmatit Sagittal Section of Part of Urogenital Tract of Cow, Showing Suburethral 



Diverticulum. 



The vulva has thick wrinkled labia, and both commissures are acute; the 

 lower one is pointed, and has on it a number of long hairs; it lies about two inches 

 (5 cm.) behind, and about the same distance below, the level of the ischial arch. 

 The glans clitoridis is small; the crura are about four inches (ca. 10 cm.) long and 

 are flexuous. The external urethral orifice or meatus urinarius is four or five 

 inches (10 to 12 cm.) from the ventral commissure. Beneath it is a blind 

 pouch, the suburethral diverticulum, which is more than an inch (ca. 3 to 4 cm.) 

 long, and readily admits the end of a finger. 



The form and position of this pouch should be carefully noted on account of the difficulty 

 it causes in catheterizing the bladder. If the catheter is passed along the ventral wall of the 

 vulva (as in the mare), it will always enter the poucli instead of the urethra. 



The glandulae vestibulares majores (or glands of Bartholin) are situated on 

 the lateral walls of the vulva, under the constrictor vulva?. They are little over 

 an inch (ca. 3 cm.) long and about half an inch (ca. 1.5 cm.) in width. Each has 

 a single duct which opens about an inch and a half (ca. 3 to 4 cm.) lateral to and 

 behind the external urethral orifice. 



The urethra of the cow is al)out four inches (10 cm.) in length ; it is narrower and 

 much less dilatable than that of the mare. It is fused dorsally with the wall of the 

 vagina, while laterally and ventrally it is covered by the constrictor vaginae muscle. 



The mammary glands, normally two in number, are popularly termed the 

 udder. They are very much larger than in the mare, and the body of each is 



