Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH) are intimately involved in the control of the growth and reproductive activities of the gonadal tissues, which synthesize and secrete male and female sex hormones. LH is a glycoprotein secreted by the basophilic cells of the anterior pituitary. Gonadotropin-release hormone (GnRH or LHRH), produced in the hypothalamus, controls the release of LH and FSH from theanterior pituitary. Like other glycoproteins FSH, TSH, and hCG, LH consists of two subunits alpha and beta. The LH binds to the theca cells and stimulates steroidogenesis in the ovary. Increased intraovarian estradiol production occurs as follicularmaturation advances, thereupon stimulating increased FSH receptor activity and FSH follicular binding. FSH, LH, and estradiol are therefore intimately related in supporting ovarian recruitment and maturation in cows.
Ovulation occurs approximately 12to 18 hours after the LH reaches a maximum level. Ovulation is fine physiological process regulated by hormones eventually releasing the egg from the ovary LH which will increase dramatically following the middle part of cycle aids the process. Thisshort period of increase in LH called hormonal surge. The LH surge also can be induced by injections of hormones like hCG to prime the ovary. This process helps in breeding of cows. For better results use Bovine milk progesterone tests (ProgeSCheck BM ) to accurately predict ovulation in cows. call 1800-745-0843 for details.