Page 485 - Anatomy and Physiology of Farm Animals, 8th Edition

470 / Anatomy and Physiology of Farm Animals

Relative to the extent of the horns, the of the uterus and ovaries, immediately
ventral to the descending colon, makes
body of the uterus is largest in the mare,
VetBooks.ir less extensive in the ruminant, and small them amenable to palpation per rectum in
in the sow. Externally, the body of the
large animals.
uterus of the cow appears larger than it is The mucosa lining the uterus, the
because the caudal parts of the horns are endometrium, is a highly glandular tissue
bound together by the intercornual liga- that varies in thickness and vascularity
ment, which obscures their individual with hormonal changes in the ovary and
nature. with pregnancy (Fig. 26‐7, see Chapter 27).
As with most other hollow internal The epithelial covering of the mucous
organs, the uterine wall consists of a membrane is of the simple columnar type
lining of mucous membrane, an interme- in the mare, but is stratified columnar
diate smooth muscle layer, and an outer epithelium in the sow and ruminants.
serous layer of peritoneum. The uterus is The uterine glands are simple
suspended bilaterally from the body wall branched tubular glands that exhibit
by the mesometrium. The mesometrium considerable coiling. These glands are
is continuous with the parietal perito- particularly active during estrus and
neum of the abdominal cavity, making the pregnancy, during which they produce a
reproductive organs retroperitoneal. The fluid colloquially known as uterine milk.
peritoneum associated with the female These glands are scattered throughout
reproductive tract, the mesometrium the endometrium of the uterus, except in
(uterus), mesosalpinx (uterine tube), and ruminants, in which the caruncles are
mesovarium (ovary), all collectively con- nonglandular. Caruncles are mushroom‐
stitute the broad ligament. The location like projections from the inner surface of

(A) (B)

1 7 1
7 5 6 4 3 5 6
4 3
2
2

8
8

(C) (D)

1 7
7 3 1
3 5 6 4 5 6 6
4 2
2
8
8

Figure 26‐6. Comparative anatomy of the female reproductive tract. (A) Cow. (B) Sow. (C) Mare.
(D) Bitch. Lateral view. 1, rectum; 2, urinary bladder; 3, cervix; 4, uterus; 5, vagina; 6, vestibule; 7, ovary;
8, mammary gland. The bitch has again been provided for comparison. Source: adapted from Reece, 2015.
Reproduced with permission of John Wiley & Sons, Inc.