[Illustration:
FIG. 417.—GENITAL ORGANS OF SOW, DORSAL VIEW. THE VAGINA AND CERVIX
UTERI ARE SLIT OPEN.
_1_, Labia vulvæ; _2_, glans clitoridis; _3_, vulva; _4_, external
urethral orifice; _5_, vagina; _5′_, cervix uteri; _6_, corpus
uteri; _7_, cornua uteri, one of which is opened at _7′_ to show
folds of mucous membrane; _8_, Fallopian tube; _8′_, abdominal
opening of tube; _9_, ovaries; _10_, ovarian bursa; _11_, broad
ligaments of uterus; _12_, urinary bladder. (From Leisering’s
Atlas.)
]
The =ovaries= are concealed in the bursa ovarii, owing to the large
extent of the mesosalpinx. They are more rounded than in the bitch, and
have a distinct hilus. They are situated usually as in the cow, but
their position is quite variable in animals which have borne young. The
surface commonly presents rounded prominences, so that sometimes the
gland has an irregular, mulberry-like aspect; this is due to the fact
that there is very little stroma and the larger Graafian follicles
project from the surface.
The =Fallopian= or =uterine tubes= are long (ca. 15 to 30 cm.), and less
flexuous than in the mare. The fimbriated extremity forms an ampulla and
has a large abdominal opening. The uterine end shades insensibly into
the small extremity of the cornu of the uterus.
The =uterus= presents several striking features. The =body= is only
about two inches (ca. 5 cm.) long. The =horns= are extremely long and
flexuous, and are freely movable, on account of the large extent of the
broad ligaments. The extremities of the horns taper to about the
diameter of the Fallopian tubes.[154] The =neck= is remarkable for its
length (ca. 15 to 20 cm.) and the fact that it is directly continued by
the vagina without forming any intravaginal projection (os uteri). It
can be distinguished by the transverse folds of its mucous membrane and
the thickness of its wall.
The changes in form and position of the uterus during pregnancy are
similar to those mentioned later in the case of the bitch.
The =vagina= is about four or five inches (ca. 10 to 12 cm.) long in a
sow of medium size. It is small in caliber, and has a thick muscular
coat which consists mainly of circular fibers. The mucous membrane is
plicated, and is intimately united with the muscular coat.
The =vulva= is relatively long. The inferior commissure is pointed and
dependent. The mucous lining is plicated. There is a small =suburethral
diverticulum=. The vestibular glands are small and variable in number.
The vestibular bulbs are little developed. The canals of Gartner may
sometimes be traced as far as the ovary, but are often difficult to
find.
The =clitoris= is long, flexuous, and pointed; beneath it is a
cul-de-sac.
The =urethra= is very long; its vulvar orifice is not concealed by a
valvular fold.
The =mammary glands= are usually ten or twelve in number, and are
arranged in two rows, as in the bitch. Each teat has commonly two
excretory ducts.