Studies On Reproductive Resomption Regulations On Cows In Postpartum

In order to understand effects of endocrine changes of cows in postpartum on ovarian functions, provide theoretical evidences for controlling early ovarian and ovarian cycles, preventing reproductive dysfunction illness and improving fertility, we studied on endocrine changes and reproductive reinstate regulations of cows in postpartum. We randomly selected 136 of 2 Oyears 1 times of parturition normally, clinical health, lactation product 7124.53 28.27kg of feeding Chinese Holstein cows in 1st, 2nd cow-farm of wulumuqi agricultural milk farm, cow-farm of xinjiang military departments. 3Iof 136 cows collected bloods samples every other day from jugular and others collected milk sample every two-day until 90d of postpartum. P4 of milk was detected by EIA; LH FSH. PRLS E2 P4 of serums were detected by RIA with clinical follow-up rectal test, detecting nutrient conditions and lactation production including: body weight.. nutrient leveL BCS. Experiment results were non-paired test. Results showed as follow. (1) 1 weeks of postpartum were resumption periods of hypothalamus-pituitary-gonad. During the period, the level of reproductive hormones was low and there were nothing structures but residual pregnancy lute in corpse and small recruited ovum. So it was relative quite period of postpartum reproductive functions. (2) From 3桽weeks of postpartum, functional actions of ovaries and reproductive hormone fluctuated easily and regulation functions of endocrine axis were usable. They were easily affected by non-endocrine factors to lead to reproductive endocrine dysfunctions and pathogenesis. This period was environment-dependence period of postpartum pier-resumption, also pathological /physiological turnover periods the best prevent and cure period of reproductive dysfu nct ions. (3) From 5--7weeks of postpartum, this was finishing period of uterine function resumption. Whether uterine function was normal or not was relate to reproductive function resumption. Even throLIh copulation, pregnancy depended on uterine resumption conditions. So this is the uteri ne-dependence period of cow reproductive function resumption.