Objectives 1. To introduce the gross anatomy of the reproductive tracts of the cow, sow, and mare. 2. To dissect the reproductive tracts of the mare, sow, and cow. 3. To develop an understanding of the functional significance of the anatomical parts of the reproductive tract
and how these parts function as aunit. ♦ Please refer to the course textbook “Pathways to Parturition and Pregnancy” to view the figures cited in this handout. The figure numbers correspond with figure numbers found in the textbook. The figures can also be found on the lab web page as part of this handout.
Gross anatomy – general terminology
1. External genitalia ♦ Vulva, Clitoris, Dorsal and Ventral Commissures, Perineum, Anus,Vestibule 2. Internal structures ♦ Vestibule, Urethra, Vagina, Urethra, Bladder, Cervix, Uterus (body/horns), Oviduct, Ovary, Broad ligament
External Genitalia (Figures 2-23, 2-24)
1. Vulva Consist of the labia majora and labia minora. Provides anatomical closure to vagina so as to minimize entry of foreign material into vagina. 2. Commissures Dorsal and ventral are the sites of the union ofthe labia. 3. Perineum Area surrounding the vulva and anus. Can be torn during a difficult parturition. 4. Clitoris Highly innervated tissue (homologous to glans penis) located in the ventral commissure that is very sensitive to tactile stimulation. Serves to control copulation in some species. 5. Vestibule Common duct for urine and fetus during parturition. Also functions to stimulate penisduring copulation. ♦ ♦ ♦ Suburethral diverticulum (also called blind pouch) Sac-like structure in cow and sow, which lies ventral to urethral opening. No know function. Urethral tubercle Bulb-like structure directly above urethral opening that protrudes into vestibule in the bitch. No know function. Vestigial glands (also called the Bartholin glands) Glands located along walls of vestibule andresponsible for viscous vaginal secretions to provide lubrication during estrus. Additionally, they produce chemicals called “pheromones”, which declare to the male that the female is in estrus. Vulvo-vaginal sphincter muscle Muscle contracts to block urine from entering the uterus.
Internal Reproductive Tract (Figures 2-4, 2-5, 2-6, 2-7, 2-8)
1. Broad Ligament Double layer of connective tissuethat originates from the peritoneum. ♦ Functions: • • ♦ • • Supports and suspends the ovaries, oviduct, uterus, cervix, and anterior vagina. Houses the vascular, lymphatic drainage, and nerve supplies. Mesoovarium Houses vascular supply, lymphatics, and nerves to ovary ♦ Forms hilus or attachment to ovary Mesosalpinx Thin tissue that supports the oviduct and helps orient infundibulum around ovaryto direct oocytes into oviduct. In the bitch, the mesosalpinx encloses the ovary forming a bursa around the ovary. Mesometrium The largest part of the broad ligament that supports the uterine horns and (or) uterine body. It is continuous with the dorsal peritoneum and hangs from the dorsal body wall.
ANS 3319C Reproductive Physiology and Endocrinology Lab -Female Reproductive Anatomy
2. Vagina ♦ ♦ Functions • • Copulatory organ during natural mating in most species & serves as birth canal during parturition. Highly acidic environment, which functions to prevent bacterial infection. ♦ ♦ • • ♦ • Microflora: aerobic and facultative anaerobic. The low pH (5.7) creates an unfavorable to the spermatozoa. Structural Characteristics:
Provideslubrication via mucous secretions and asserts pressure on the penis to stimulate ejaculation during mating is some species. Stimulates the bull’s penis directly via temperature. Poorly defined muscular layer but a well developed and highly adapted mucosal layer composed of epithelium, which changes in thickness depending on the endocrine environment as the animal progresses through the estrous cycle....