Cervix

Question 1

Cervix Function

Answer 1

Is gatekeeper of upper female tract – sits between cranial vagina & uterus.
Functions:
- Produce mucus
- Select high quality sperm
- Flush out sperm/pathogens after mating
- Form barrier during pregnancy (aseptic uterine env).

Cervix sealed by mucus plug during pregnancy

Question 2

Cervix structure

Answer 2

Part of long canal. Includes:
- Central lumen (canal)
- Single (bitch, queen) or multiple (cow, ewe,mare, sow) folds/rings protruding into lumen
Has 2 openings (os)
- Internal cervical os at uterine end &
- Opening into vagina is the external cervical os – becomes red, wet & relaxed in receptive females (due to hormonal influence)

Note: os will relax (open) to allow for passage of sperm when receptive

Question 3

Species differences in cervical structure (cow, ewe, mare)

Answer 3

Bull – ejaculate at external cervical os, can pass inseminating pippete through cervix for artificial breeding
Ewe = cartilaginous rings, ejaculate at external cervical os but not possible to pass inseminating pipette through cervix
Mare = no rings, stallion penis enters lower cervix during mating, VERY easy to pass inseminating pipette through cervix in mare

Question 4

Species differences in cervical structure (sow, bitch)

Answer 4

Sow = highly developed cervical rings
Bitch = very easy to pass inseminating pipette through into uterus

Question 5

Cervical regions

Answer 5

2 distinct regions (ecto and endo)

• Mucosa protruding into vagina = ectocervix
• Mucosa lining canal = endocervix

Endocervix is columnar epithelium, which secretes cervical mucus
Ectocervix (protrudes into vagina) is stratified squamous epithelium (like vagina)

Question 6

Cervical epithelium

Answer 6

Transition between endo/ectocervix (columnar/squamous epithelium) can be ABRUPT & OBVIOUS
Will know you’ve hit endocervix when you see cervical glands.

Question 7

Cervical crypts

Answer 7

In cervical canal, mucosa form deep crypts which contain mucus producing cells (goblet cells)