Transitory changes in plasma progestins, estradiol, and luteinizing hormone approaching ovulation in the bovine.

@article{Chenault1975TransitoryCI,
  title={Transitory changes in plasma progestins, estradiol, and luteinizing hormone approaching ovulation in the bovine.},
  author={J. R. Chenault and W. Thatcher and Pushpa S. Kalra and Robert M. Abrams and Charles J. Wilcox},
  journal={Journal of dairy science},
  year={1975},
  volume={58 5},
  pages={
          709-17
        }
}
Progestins, estradiol, and luteinizing hormone were measured by radioimmunoassay in bovine plasma samples collected from indwelling jugular catheters daily on days minus 6 to minus 4, every 6 h on days minus 3 and minus 2, and every 2 h from day minus 1 to ovulation. Least squares analyses characterized time trends within animals and interrelationships between these hormones. Plasma progestins decreased from 5.7 ng/ml at day minus 6 to .07 ng at the peak of luteinizing hormone. No preovulatory… 
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TLDR
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TLDR
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Decline in Circulating Estradiol During the Periovulatory Period Is Correlated with Decreases in Estradiol and Androgen, and in Messenger RNA for P450 Aromatase and P450 17α-Hydroxylase, in Bovine Preovulatory Follicles1
TLDR
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Changes of luteinizing hormone and progesterone for dairy cows after gonadotropin-releasing hormone at first postpartum breeding.
TLDR
Cows treated with gonadotropin-releasing hormone that conceived had higher progesterone than other cows, and that was evident at the first 4 days postbreeding.
Relationship of plasma testosterone concentrations to pituitary-ovarian hormone secretion during the bovine estrous cycle and the effects of testosterone propionate administered during luteal regression.
TLDR
It is concluded that concentrations of testosterone present in plasma have the capacity to alter the interval between luteal regression and subsequent ovulation by direct influence on ovarian aromatization processes.
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