Veterinary Physiology-III

FUNCTIONS

Action on the CNS

• Promotes the female sex behaviour and growth of female reproductive tract
• To induce behavioural estrus in the female but small amount of progesterone with estrogen is needed to induce estrus.
• Regulates the release of FSH and LH from the anterior pituitary by its feed back mechanism.

Action on the uterus

• It aids in sperm transport by increasing the myometrial contractions. Estrogen priming promotes the growth of the endometrial glands. Necessary for maintenance of zygote and helps implantation of zygote.
• 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.

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.