Lack of LH response to exogenous estradiol in heifers with ACTH-induced ovarian follicular cysts.

نویسندگان

  • A Y Ribadu
  • K Nakada
  • Y Tanaka
  • M Moriyoshi
  • W C Zhang
  • T Nakao
چکیده

The aim of the present study was to examine the LH response to exogenous estradiol in 4 heifers with ACTH-induced ovarian follicular cysts. During the control experiment, administration of estradiol 24 hr after PGF2alpha in luteal phase heifers resulted in a LH response in all 4 heifers. The LH response was obtained between 16-20 hr after estradiol administration. The peak LH concentration (Mean +/- SEM; 5.1 +/- 0.8 ng/ml) during the control study was significantly different (P<0.05) from the concentration after cyst formation. None of the 4 heifers responded to estradiol after ovarian cyst formation. This result suggests that heifers with ACTH-induced ovarian follicular cysts may have a defective hypothalamio-pituitary response to exogenous estradiol similar to cows with spontaneous ovarian cysts.

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عنوان ژورنال:
  • The Journal of veterinary medical science

دوره 61 8  شماره 

صفحات  -

تاریخ انتشار 1999