Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Apr 28;12(9):1140.
doi: 10.3390/ani12091140.

Follicular Size Threshold for Ovulation Reassessed. Insights from Multiple Ovulating Dairy Cows

Fernando López-Gatius  1   2 , Mònica Llobera-Balcells  3 , Roger J Palacín-Chauri  3 , Irina Garcia-Ispierto  2   3 , Ronald H F Hunter  4   5
Affiliations

Follicular Size Threshold for Ovulation Reassessed. Insights from Multiple Ovulating Dairy Cows

Fernando López-Gatius et al. Animals (Basel). .

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.

Keywords: bovine; follicular size; ovulation failure; pregnancy rate; twins.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

References

    1. Mee J.F. Factors affecting the spontaneous twinning rate and the effect of twinning on calving problems in nine Irish dairy herds. Irish Vet. J. 1991;44:14–20.
    1. Cuttance E., Laven R. Perinatal mortality risk factors in dairy calves. Vet. J. 2019;253:105394. doi: 10.1016/j.tvjl.2019.105394. - DOI - PubMed
    1. López-Gatius F. Twins in dairy herds. Is it better to maintain or reduce a pregnancy? Animals. 2020;10:2006. doi: 10.3390/ani10112006. - DOI - PMC - PubMed
    1. Nielen M., Schukken Y.H., Scholl D.T., Wilbrink H.J., Brand A. Twinning in dairy cattle: A study of risk factors and effects. Theriogenology. 1989;32:845–862. doi: 10.1016/0093-691X(89)90473-1. - DOI - PubMed
    1. Echternkamp S.E., Gregory K.E. Effects of twinning on gestation length, retained placenta, and dystocia. J. Anim. Sci. 1999;77:39–47. doi: 10.2527/1999.77139x. - DOI - PubMed

LinkOut - more resources