Veterinary Anatomy of Urinary system (pelvic peritoneal excavations) and specie difference between different species

1. URINARY SYSTEM Pelvic Peritoneal Excavations

2. PELVIC PERITONEAL EXCAVATIONS IN MALE ANIMALS
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3. Pelvic peritoneal excavations in female animals
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4. DEFINITIONS OF THE GIVEN TERMS
MESORECTUM: The short mesentery suspending the rectum from the dorsal wall of the
pelvic cavity.
RECTUM: The large intestine within the pelvic cavity, extending from the descending
colon to the anal canal.
URINARY BLADDER: The greatly distensible pouch receiving and storing the urine from
the kidneys for release out the urethra. The empty bladder lies about within the pelvic
cavity but with distention extends into the abdominal cavity. The bladder has a free
apex, a body and a neck.
LIGAMENTS OF THE BLADDER: The connecting peritoneum between the bladder and
pelvic wall. They are of two type:-
-Lateral Ligament: They are two in number. They connect the sides of the bladder to the
lateral pelvic wall.
-Lateral Ligament with umbilical arteries: It is actually the round ligament that travels in
the edge of the lateral ligament, and round ligament is the remnant of the umbilical
arteries of the foetus.
-Median Ligament: It is also called as ventral ligament. It reflects from the bladder’s
ventral surface to the pelvic floor and abdominal wall. It carries urachus in foetus.

5. DEFINITIONS OF THE GIVEN TERMS
VESICULAR GLANDS: They are the paired accessory sex glands. They are located
dorsolateral to the neck of the bladder. They secrete and alkaline fluid rich in
fructose into the urethra. They are present in the stallion, ruminants and boar.
DUCTUS DEFERENS (Deferent Duct/vas deference): It is the continuation of the
epididymal duct at the tail of the epididymis. It travels beside the body of the
epididymis and, up the spermatic cord, and through the inguinal canal to reach the
abdomen. In abdomen, it arches caudally to the pelvic cavity passing through the
prostate gland to open into the pelvic urethra.
Epidydymis  DEFERENT DUCT spermatic cord  abdomen through inguinal canal
 pelvic cavity  prostate gland  URETHRA
UTERUS MASCULINUS (persistent Mullerian duct) is a vestigial embryological
remnant of the paramesonephric duct system in males and has been associated with
clinical signs such as dysuria, incontinence, and urethral obstruction in dogs.
 The uterus masculinus develops in the embryo from the lower part of the mullerian duct.
 In number of animals it becomes the prostatic utricle, which fills the prostate glands with secretion
during the sexual activity.

6. DEFINITIONS OF THE GIVEN TERMS
UROGENITAL FOLD: They are derived from the cloacal folds (lateral elevation of
cloacal membrane).
In male embryos, they close over the urethral plate and fuse to form the spongy
urethra and ventral aspect of the penis.
In female embryos, the unfused urogenital folds develop into the labia minora.
The PERITONEAL CAVITY is completely closed in the male, but in the female there is
an opening at the abdominal end of each uterine tube and therefore there is a
communication with the external genitalia and the peritoneal cavity. There are
several pelvic peritoneal pouches:-
· Vaginal process (processus vaginalis peritonei),
· Pubovesical pouch (excavatio pubovesicalis),
· Vesicogenital pouch (excavatio vesicogenitalis) and
· Rectogenital pouch (excavatio rectogenitalis).

7. DEFINITIONS OF THE GIVEN TERMS
VAGINAL PROCESS: In all male domestic animals and in the female dog, the
peritoneum and the transverse fascia extend through the inguinal canal to line the
vaginal process. In the vaginal process the testis will be drawn during the process of
testicular descent. In the bitch it contains the round ligament of uterus which
corresponds to the gubernaculum testis in male animals.
PUBOVESICLE POUCH: It is formed by a reflection of a peritoneum from the floor of
the pelvis onto the neck of the bladder. It is divided into two compartments by the
central ligament of the urinary bladder.
VESICOGENITAL POUCH: The peritoneal pouch between the bladder and the genital
fold in the male or the uterus in the female.
RECTOGENITAL POUCH: The pouch contained by the extension of the peritoneal
cavity into the pelvic cavity between the rectum and the uterus or the uterus
masculinus in the male.
In males there is a communication between the rectogenital and the vesicogenital
pouch.

8. DEFINITIONS OF THE GIVEN TERMS
PARARECTAL FOSSA are the two dorsolateral extensions of the rectogenital pouch,
next to the mesorectum. It is a peritoneal depression on either side of the rectum
formed by peritoneal folds. The fossa is a lateral extension of the male rectovesical
pouch or the female rectouterine pouch
The caudal part of the pelvic cavity does not have a peritoneal lining and, is
referred to as the retroperitoneal part.
The outlet of the pelvic cavity is closed by the perineum.