Female repro

• Mammalian female reproductive organs

  • Ovary
  • Oviduct
  • Uterus
  • Vagina
  • Vulva
  • Mammary gland
• Ovary


  • Homologous to the testes
  • Perform both endocrine and exocrine functions
  • Covered by surface epithelium modified from visceral peritoneal coverings
  • Consists of cortex and medulla (reversed in mares)
• Oogenesis


  1. Mitosis

  2. Meiosis
• Mitosis


  Oogonia proliferate from primordial germ cells, divide and give rise to more oogonia
• Meiosis


  • Oogonia entering prophase of 1st meiotic division become primary oocytes
  • Primary oocytes are arrested at this stage until sexual maturity
  • 1st meiotic (reductional) division occurs at puberty/sexual maturity
  • 2nd meiotic (equational) division occurs when a spermatozoon penetrates the zona pellucida
• Follicular development (folliculogenesis)


  1. Primordial

  2. Primary

  3. Secondary

  4. Mature (pre-ovulatory)
• Primary (quiescent) follicle


  Primary oocyte surrounded by single layer of follicular cells
• Secondary follicle


  • Primary oocyte surrounded by several layers of follicular cells (membrana granulosa)
  • Stromal cells differentiate into theca folliculi interna and theca folliculi externa
• Tertiary (vesicular) follicle


  • Fluid-filled vesicular spaces begin to appear between granulosa cells, coalescing to form follicular antrum filled with liquor folliculi
  • Primary oocyte surrounded by granulosa cells forming cumulus oophorus
  • Granulosa cells adjacent to primary oocyte become columnar forming corona radiata
• Pre-ovulatory (mature) follicle


  • Enlarged structures extending from surface to depths of cortex
  • Have large antrae
• Ovulation


  1. Rupture of follicle and release of oocyte

  2. Enzymatic hydrolysis of connective tissue components

  3. Thinning of thecal investments and cortical components

  4. Follicle ruptures through follicular stigma

  5. Liquor folliculi released probably aids transport of oocyte to infundibulum
• Follicular atresia


  • Degeneration of follicles that do not terminate in ovulation
  • In early stages, degeneration does not result in scar tissue
  • In advanced stages, leads to formation of corpus atreticum (scar tissue)
• Interstitial gland


  • Polyhedral, epithelioid cells within ovarian stroma
  • Characteristics of steroid producing cells similar to corpus lutein cells
• Hilus cells


  Located at hilus of ovary, similar to interstitial cells of testis
• Corpus luteum formation


  1. Corpus haemorrhagicum forms first

  2. Follicular walls collapse

  3. Granulosa cells protrude into residual lumen

  4. Haemorrhage accompanying ovulation forms clots

  5. Granulosa cells proliferate, hypertrophy and transform into granulosa lutein cells

  6. Theca interna cells convert to theca lutein cells (luteinization)
• Corpus luteum


  Yellow body formed from transformed granulosa and theca lutein cells
• If fertilization does not occur

  Corpus luteum is converted to corpus albicans
• If fertilization occurs


  Gravid corpus luteum (corpus graviditalis) persists and remains active for a period of time during pregnancy
• Parts of uterine tube (oviduct)


  • Infundibulum
  • Ampulla
  • Isthmus
• Uterine tube epithelium


  Intermittently ciliated simple columnar epithelium (may be pseudostratified in sows and cows)
• Uterine tube


  • Tunica mucosa of ampulla is highly folded
  • Kinocilia assist in movement of ova along folded tunica mucosa
  • Lamina propria-submucosa consists of loose collagenous tissue devoid of glands
  • Tunica muscularis best developed in isthmus
  • Tunica serosa with many blood vessels forming vascular layer
• Parts of uterus


  • Body
  • Horns
  • Neck (cervix)
• Uterine forms


  • Bicornuate uterus (most species)
  • Uterus simplex (primates)
  • Bipartite uterus (carnivores)
  • Duplex uterus (lagomorphs, monotremes, marsupials)
• Layers of uterine wall

  • Endometrium
  • Myometrium
  • Perimetrium
• Infundibulum


  This is where fertilization occurs
• Epithelium


  • In most species is intermittently ciliated simple columnar epithelium
  • In sows and cows, it may be pseudostratified intermittently ciliated columnar epithelium
• Ampulla


  • The tunica mucosa is highly folded
  • The kinocilia assist in the movement of ova along the highly folded tunica mucosa
• Lamina propria-submucosa


  • Consists of loose collagenous tissue devoid of glands
• Tunica muscularis


  • Best developed in the isthmus
• Tunica serosa


  • Typical with many blood vessels forming a vascular layer
• Uterus Functions


  • Semen deposition
  • Uterine contractions are essential for transport of spermatozoa
  • Site of development of the embryo and fetus
• Uterus Forms


  • Bicornuate uterus - uterus with a body, 2 horns and a single cervix
  • Uterus simplex - uterus with a prominent body, 2 small horns & a single cervix
  • Bipartite uterus - 2 large separate horns entering the vagina via a single cervix
  • Duplex uterus - uterine horns are completely separated and enter the vagina by separate cervix
• Uterine Wall Layers


  • Endometrium
  • Myometrium
  • Perimetrium
• Endometrium


  • Epithelium is simple columnar although patches of pseudostratified (sows, cows) and cuboidal may occur
  • Uterine glands are simple/branched tubular
  • Lamina propria-submucosa consists of loose collagenous tissue. In ruminants, particular regions, caruncles, are highly vascularized
• Myometrium


  • Has both thick inner circular and thin outer longitudinal coats of smooth muscles that continues into the mesometrium
  • A vascular layer occurs between the two muscle layers
• Cervix


  • Acts as a valve closing the uterine lumen from the vagina
  • In sows - thin-walled, in cows - thick-walled
  • Lining cells in cows are glandular secreting clear mucus during estrus and forming a strong cervical seal during pregnancy
  • Epithelium - stratified squamous in canines; primarily gobletlike cells in bovines, with some kinociliated columnar cells in a few species
  • Endocervix - lined by simple columnar, ectocervix is lined by stratified squamous epithelium
  • Lamina propria-submucosa - varies from loose to dense collagenous tissue during estrus cycle
  • Tunica muscularis - well developed
• Vagina


  • Epithelium - non-glandular stratified squamous epithelium
  • In cows, isolated foci of goblet cells are present in the cranial part
  • In bitches, intra-epithelial glands have been observed during estrus
  • Tunica mucosa and tunica submucosa are highly folded
  • Lamina propria-submucosa consist of loose collagenous tissue
  • Tunica muscularis consists of 3 layers; inner longitudinal, middle circular and outer longitudinal
  • Tunica serosa is present cranially and continues caudally as tunica adventitia
• Vulva


  • Consists of labia and vestibule
  • Labia - folds of integument composed of integumentary structures and epithelium is stratified squamous keratinized epithelium
  • Vestibule - similar to the caudal part of the vagina. Epithelium is non-keratinized stratified squamous epithelium
  • Lamina propria-submucosa - loose & dense collagenous tissue rich in elastic fibres. Vestibular glands are present
  • Tunica muscularis has inner longitudinal and outer circular layers. The outer layer consists of 2 muscles; constrictor vestibuli and constrictor vulvae
  • Tunica adventitia is typical
• Clitoris


  • Homologous to male penis and consists of body, glans and preputial coverings
  • Body - contains cavernous tissue, corpus cavernosum clitoridis
  • Glans clitoridis - may contain cavernous tissue (bitches & mares) or highly vascular loose collagenous tissue
  • Preputial covering - glandular and hairless reflection of the vestibular cutaneous mucous membrane
• Urethra


  • Lined by transitional epithelium near the external urethral orifice, it changes to stratified squamous epithelium
  • Lamina propria-submucosa - varies from loose to dense collagenous tissue
  • Tunica muscularis - has 2 or 3 layers of smooth muscles cranially and caudally, the smooth muscles become intermingled with skeletal muscles