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Updated: Sep 23, 2025

Isolation of Small Preantral Follicles from the Bovine Ovary Using a Combination of Fragmentation, Homogenization, and Serial Filtration
Published on: September 27, 2022
Follicular Size Threshold for Ovulation Reassessed. Insights from Multiple Ovulating Dairy Cows
Fernando López-Gatius1,2, Mònica Llobera-Balcells3, Roger J Palacín-Chauri3
1Transfer in Bovine Reproduction SLu, 22300 Barbastro, Spain.
Abstract:
In Bos. taurus cattle, follicular deviation to dominance begins when the selected ovulatory follicle reaches a mean diameter of 8.5 mm. The dominant follicle acquires the capacity to ovulate when it reaches a diameter of about 10 mm. In this study, data derived from 148 cows in estrus with one follicle of ovulatory size and another of 7-9 mm, reveal that the small follicle has the capacity to ovulate alone or with the dominant follicle; thus, giving rise to a single or twin pregnancy. This indicates that a follicle of deviation size may ovulate in the presence of a follicle of ovulatory size.
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