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Updated: Jul 9, 2026

A Modified Co-Culture System for Understanding Granulosa-Theca Cell Interactions in the Bovine Ovary
Published on: September 19, 2025
Follicular and steroid hormone changes in Arabian mares in the postpartum period
Mehmet Can Gündüz1, Güven Kaşikci, Bülent Ekiz
1The Institute of Medical Sciences, University of Istanbul, Cerrahpasa, Istanbul, Turkey. mcg@istanbul.edu.tr
Abstract:
In this study, the aim has been to characterize the profiles of progesterone, estradiol and follicular changes during postpartum period from parturition to first postpartum ovulation. Jugular venous blood was taken daily for progesterone and estradiol assay until first postpartum ovulation. The diameters of the follicles of the ovaries were recorded. The mean progesterone and estrogen concentrations markedly decreased (p<0.05) during the 48h after parturition. No correlation was observed between estradiol concentrations and the diameter of the largest follicle whereas a negative correlation was present between the number of follicles smaller than 20mm and the number of follicles larger than 20mm on the third and fourth days after postpartum.
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