The right uterine cornu and the vagina and vulva are opened up: _1_,
Labium vulvæ; _2_, ventral commissure; _3_, glans clitoridis; _4_,
glandula vestibularis major, exposed by slit in mucous membrane;
_5_, opening of duct of preceding; _6_, suburethral diverticulum;
_7_, external urethral opening; _8_, openings of canals of Gartner;
_9_, os uteri; _10_, corpus uteri; _11_, cornu uteri; _12_,
cotyledons; _13_, Fallopian tube; _14_, ostium abdominale tubæ;
_15_, ovary (From Leisering’s Atlas, reduced.)
]
The =broad ligaments= are not attached in the sublumbar region as in the
mare, but to the upper part of the flanks, about a handbreadth below the
level of the external angle of the ilium. They contain a conspicuous
amount of unstriped muscle. The =round ligaments= are well developed,
and can be traced distinctly to the vicinity of the internal inguinal
ring.
The =vagina= is somewhat longer and more roomy than that of the mare;
its wall is also thicker. Its average length in the non-pregnant animal
is about 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 vaginæ
in oöphorectomy.
In the ventral wall of the vagina, between the muscular and mucous
coats, there are frequently present the two =canals of Gartner= (Ductus
epoöphori longitudinales). When well developed they 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 fœtal
vestiges, are very variable. Röder 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.
[Illustration:
FIG. 415.—DIAGRAMMATIC 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 pouch instead of the urethra.
The =glandulæ vestibulares majores= (or glands of Bartholin) are
situated on the lateral walls of the vulva, under the constrictor vulvæ.
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 about 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 vaginæ 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 somewhat ellipsoidal in form, but flattened transversely. The =base=
(or dorsal surface) of each gland is slightly concave and slopes
obliquely downward and forward in adaptation to the abdominal wall, to
which it is adherent; posteriorly it is in relation to the large
supramammary lymph glands and a quantity of fat. The inner surface is
flat, and is separated from the other gland by a well-developed double
septum. The outer surface is convex. Four well-developed teats are
present; they average about three inches (ca. 7 to 8 cm.) in length. It
is customary to consider the udder to consist of four “quarters.” There
is no septum nor visible division between the two quarters of the same
side, but, on the other hand, injections of fluids of different colors
into the two teats of the gland demonstrate that the cavities drained by
them do not communicate.
[Illustration: