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In Vitro Culture Strategy for Oocytes from Early Antral Follicle in Cattle
Published on: July 8, 2020
Follicle selection in cattle: follicle deviation and codominance within sequential waves
L J Kulick1, D R Bergfelt, K Kot
1Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA.
Biology of Reproduction
|August 22, 2001
Summary
Bovine follicle deviation mechanisms are similar between follicular waves 1 and 2. However, waves with codominant follicles show distinct hormonal and follicle dynamics compared to single dominant follicle waves.
Area of Science:
- Reproductive Biology
- Endocrinology
- Veterinary Science
Background:
- Follicle deviation is key in bovine follicular waves, determining dominant follicle selection.
- Understanding deviation differences between early (wave 1) and later (wave 2) follicular waves is crucial for reproductive insights.
Purpose of the Study:
- Compare follicle deviation characteristics in wave 1 versus wave 2 in cattle.
- Investigate hormonal profiles and follicle dynamics associated with single versus codominant follicle development.
Main Methods:
- Compared follicle diameters (F1, F2, F3) and deviation timing in wave 1 and wave 2.
- Monitored circulating FSH, LH, estradiol, and inhibin concentrations during deviation.
- Analyzed differences between waves with single dominant follicles and codominant follicles.
Main Results:
- No significant differences in follicle diameters or deviation timing were found between wave 1 and wave 2.
- Both waves showed decreasing FSH, increasing estradiol, and decreasing inhibin post-deviation, with a transient LH peak.
- Codominant follicle waves were more frequent in wave 1 and exhibited altered estradiol and FSH/LH dynamics.
Conclusions:
- Follicle deviation mechanisms are conserved between bovine follicular waves 1 and 2.
- Codominant follicle development is associated with distinct hormonal milieu and follicle dynamics, particularly in wave 1.
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