Estrogen and progesterone are the two main ovarian hormones. Estrogen is produced primarily in the ovaries and stimulates the development of female reproductive organs and secondary sex characteristics. It also regulates the female estrus cycle. Progesterone is produced in the ovaries and placenta during pregnancy. It prepares the uterus for pregnancy and maintains pregnancy by supporting embryo development. Both hormones work together to regulate the female reproductive system.

1. WELCOME

2. OVARIAN HORMONE-
ESTROGEN & PROGESTERONE
Surya Adhikari
B V SC & AH, NEPAL
Suryaadhikari313@gmail.com

3. INTRODUCTION
• Ovary is the primary female sex organ that produces two
main steroid hormones.
• Estradiol - Steroid
• Progesterone- Steroid
• Androgen-Steroid
• Relaxin- Protein
• These hormones exert their action on the female genital
tract and mammary gland.
• Note- Progesterone & Relaxin is only found in female.

4. ESTROGEN

5. • The estrogens are steroidal hormones synthesized from cholesterol and
produced primarily by the ovaries, placenta and corpus luteum.
• A significant source of estrogens is the testes of stallions and boars,
while a minor source is the adrenal gland.
• The estrogens are metabolized by the liver and excreted in the bile, feces,
and the urine (horses and ruminants).
• Progesterone decreases the effects of the estrogen and FSH and LH may
be involved in estrogen secretion.

6. SOURCES OF ESTROGEN
• Granulosa cells of ovarian follicle, placenta, and corpus luteum.
Adrenal cortex also produces estrogen.
• Estradiol – predominates in non-pregnant animals
• Estrone – predominates in pregnant animals
• Estriol – predominates in pregnant primates
• Plant estrogen is also found in legumes – Clover and Alfa Alfa
which cause infertility in animals.
• Binding proteins in the circulation carry estrogen.

7. FUNCTIONS OF ESTROGEN
• Maturation growth and development of the reproductive organs.
• Stimulation of normal physiological processes of the tubular reproductive
tract.
• growth of the uterine muscle
• development of the endometrial lining of the uterus
• increase the vascularity of the uterus
• Induction of behavioral estrus
• Dilation of the cervix, liquefaction of mucous plug.
• Under the influence of the estrogens the uterus is less susceptible to
infection.

8. • It aids in sperm transport by increasing the Myometrial contractions.
• The estrogens inhibit the secretion of FSH and LH via a negative feedback
mechanism
• The estrogens are involved in the regression of the corpus luteum.
• Estrogen priming promotes the growth of the endometrial glands.
• Necessary for maintenance of zygote and helps implantation of zygote.

9. • At the time of parturition, it sensitizes the pregnant uterus to oxytocin,
thus aid the uterine contraction along with oxytocin and PGF2α. for the
expulsion of fetus.
• Estrogen increase the rate of migration of leukocytes into the uterine
lumen, and thus increases the bactericidal activity of the uterus during
estrum.
• Estrogen priming promotes the growth of the endometrial glands.
Necessary for maintenance of zygote and helps implantation of zygote.
• Regulates the release of FSH and LH from the anterior pituitary by its
feedback mechanism.

10. Secondary sexual characters
• Estradiol is responsible for the secondary sex characteristic of the
female
• It causes the growth of the duct system of the mammary gland
• It stops growth of long bones by initiating the closure of epiphyseal
growth plate
• It causes disposition and distribution of body fat.
• They are required for the development of the secondary sex
characteristics of the female including hair growth, deposition of body
fat, mammary gland development, plumage, etc.
• Protein anabolism in ruminants
• They play a role in the normal health and function of the skin

11. SUMMARY- EFFECTS OF ESTROGEN ON
REPRODUCTIVE TRACTS
• VAGINA- slight mucous secretion, hyperemia, oedema
• CERVIX – Relaxation, Liquefaction of mucous plug
• UTERUS- Stimulates uterine gland development, sensitization of the
endometrium to oxytocin, immune activation (local), leucocyte
infiltration, secretion of the PGF2alpha and PGE2
• FALLOPIAN TUBE-Increased motility & cilia activity
• MAMMARY GLAND- Stimulates mammary duct development
• CORPUS LUTEUM- Leutolytic (bovine & ovine) but leucotrophic
(equine and porcine)

12. SIDE EFFECTS
• Prolonged use or large doses can produce cystic ovaries or ovarian
atrophy
• Because of its effect on the ligaments, the estrogens predispose to
prolapse of the vagina and rectum and dislocations and fractures of the
pelvic bones.
• In the dog excessive amounts or prolonged administration of estrogens
can produce a fatal anemia - leukopenia and thrombocytopenia.
• In some species the estrogens in combination with progesterone may
increase the incidence of cystic endometrial hyperplasia - pyometra
complex.

13. ESTROGEN - COMMERCIAL USE
• In ruminants, estrogen also have a protein anabolic effect to increase body weight gain and
growth. The possible mechanism for increased growth may be due to the ability of estrogens
to stimulate the pituitary to release more growth hormone.
• Diethyl stilbesterol – a synthetic nonsteroidal estrogen was formerly used for growth
promotion.
• Estrogen have been used to abort cows and sheep because of their luteolytic property.
• Regression of CL
• Treatment
• Post partum metritis
• Retained placenta
• Mummified fetus
• Pyometra
• It is epitheliotropic and causes growth of soft skin. So used in ointments in skin ailments,
produce cornification of vaginal epithelial in certain type of vaginitis.

14. INDICCATIONS
• They are used to evacuate the uterus in cases of fetal mummification, fetal
maceration and Pyometra.
• They are used to induce abortion in all species
• They can be used in the treatment of postpartum metritis and retained fetal
membranes
• Used in the management of misalliance in dogs
• To produce signs of estrus in anestrual animals
• Treating cases of estrogen responsive urinary incontinence

15. • In virgin heifers and dry cows estrogen can be used to stimulate
mammary development and lactation
• Large doses of estrogen after parturition can be used to inhibit lactation
and relieve congestion of the mammary glands.
• Used as growth promotants in beef cattle
• Used in the management of skin condition in spayed bitches
• In treating male dogs with prostatic hyperplasia
• Can be used to decrease libido in males

16. PROGESTERONE
These include the naturally occurring steroid progesterone
which is synthesized from cholesterol and produced by the
corpus luteum (main source), placenta (especially of the ewe
and mare after the first 1/3 and 1/2 of gestation respectively),
the adrenal gland and the testes, as well as a number of
synthetic progesterone which are much more potent and have a
longer half-life than progesterone.

17. SOURCES
• Luteal cells of corpus luteum
• Also produced from adrenal cortex and placenta.

18. FUNCTIONS
• Progesterone causes growth of the glandular system of the endometrium of
the uterus, and the secretions from the endometrial glands (uterine milk)
for the nutrition of the ovum and the attachment of the embryo.
• Progesterone plays a role in the maintenance of pregnancy (and
pseudopregnancy) by providing a favorable environment for survival of
the embryo.
• Progesterone causes growth of the alveolar system of the mammary gland.
• Progesterone inhibits the smooth muscle activity of the uterus - renders it
less sensitive to oxytocin.

19. • Target tissues are relatively insensitive to progesterone unless primed
by estrogen - At low levels progesterone acts with estrogen to
stimulate ovulation by promoting LH release.
• At high levels progesterone inhibits the secretion of FSH and LH via a
negative feedback and thus also prevents the ovulation of follicles
during the luteal phase and during pregnancy.
• Progesterone increases the efficiency of nutrient utilization.

20. EFFECTS ON PEPRODUCTIVE ORGANS
• Vagina- slight mucous secretion, paleness, exfoliation
• Cervix- Closure, formation of mucous plug
• Uterus- stimulates uterine gland secretions, sensitization of
endometrium to oxytocin, decreases uterine motility, inhibition of
PGF2 alpha & PGE2.
• Fallopian tube- increased secretion , decreased motility
• Mammary gland – Stimulates lobulo-alveolar development

21. APPLICATIONS
• Prevent or control habitual abortion due to an actual or possible
progesterone deficiency.
• Estrum deferment or suppression in the ewe, cow, sow, mare and bitch.
• Synchronization of estrus in the mare, ewe, cow and sow.
• In heifers the progestins are used to promote growth - suppresses heat

22. • To treat post-partum hemorrhage in the bitch.
• In cats progesterone has been used to treat miliary eczema and
eosinophilic granulomas.
• Progesterone has a calming as well as androgenic effect and has been
used to manage antisocial or aggressive behavior in mares, stallions,
dogs and cats.

23. THANKS