FEMALE REPRODUCTIVE SYSTEM-RABBIT

The female reproductive organs include a pair of ovaries, a pair of oviducts, a pair of uteri, vagina, vestibule, clitoris and some accessory glands.

The two ovaries are small, whitish, oval bodies, about 2 cm long.
They are found behind the kidneys, each ovary attached to the dorsal abdominal wall by a double fold of peritoneum called mesovarium.
From the surface of ovaries project several blister-like, small, rounded, semitransparent projections, called ovarian or Graafian follicles, each containing a developing ovum.
Histologically, the section of a rabbit ovary shows a peripheral layer of germinal epithelial cells surrounding a dense mass of connective tissue fibres, called stroma, containing blood andlymph vessels and nerve.
Stroma contains groups of actively dividng germinal cells, called follicle in various stages of development.
In each follicle, a single cell enlarges firswhile others surround and nourish it. It ultimately beomes oocyte orovum.
The mass of cells around oocyte is known as discusproligerous.
When ripe, the follicles are known as Graafian follicles, which project from thesurface of ovary as minute bumps.
Each graafian follicle contains a large fluid - filled follicular cavity.
The cells lining the cavity are termed membrana granulosa.
The fully mature oocyte is surrounded by a thick transparent membrane called zona pellucida containing yolk and fat droplets.
It is covered by another striated layer ot columnar cells, called corona radiata.

In the stroma there are also found groups of interstitial cells which produce sex hormones (oestrogen).
Eventually each mature follicle bursts to liberate the oocyte into body cavity, a process known as ovulation.
The follicular cells remaining behind divide rapidly to form a yellowish solid mass of cells called corpus luteum.
During pregnancy it serves as a temporary endocrine gland secreting a hormone (progesterone).
It causes uterus to enlarge to receive the growing foetus and stimulates lactation.
If ovum is not fertilized, corpus luteum gradually disappears leaving a scar called corpus albicans.

Each oviduct opens anteriorly, close to the outer border of the ovary of its side, by a wide funnel called fallopian or oviducal funnel.
The opening of funnel, or ostium, is provided with many cilia to receive the minute ova released from the ovary.
Funnel leads into the upper part of oviduct. It is a short, narrow, coiled and internally ciliated duct called fallopian tube. Ova pass. through this tube by ciliary action and fertilization also occurs here.
The fallopian tube is followed by a much wider, longer convoluted, thick walled muscular tube the uterus.
It is richly vascular and highly distensible and attached to the dorsal abdominal wall by a mesentery.
Fertilized ova or zygotes get implanted on the uterine wall to develop into embryos or foetuses, each attached to the placenta by an umbilical cord.

The uteri of both the sides meet into a long wide, median duct, the vagina, lying dorsally upon the urinary bladder.
It opens posteriorly into the neck of bladder to join the urethra forming a short narrow common urinogenital canal or vestibule.
It runs backwards ventral to the rectum and opens to the exterior by a slit-like aperture, the vulva.
The vagina serves to receive the penis of the male during copulation.

From the anterior wall of vulva projects a small erectile knob-like clitoris.
It is regarded homologous with the male penis since it contains a pair of erectile tissue, the corpora cavernosa.
But the urethra does not pass through the clitoris.

In the female rabbit, there is no prostate gland.
A pair of small Bartholin’s glands or Cowper’s glands lies embedded in the dorsal wall of vestibule.
Their viscid secretion lubricates the vaginal passage. The perineal and rectal glands are as in the male.

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