Follicle deviation in ovulatory follicular waves with one or two dominant follicles in mares.
Abstract: The follicle and hormone aspects of diameter deviation and development of one dominant (>/=28 mm) follicle (1DF) vs two dominant follicles (2DF) were studied in 32 ovulatory follicular waves in mares. Follicles were ranked each day as F1 (largest) to F3. The beginning of deviation was designated day 0 and preceded the first increase in the differences in diameter between F1 and F2 in the 1DF group and between a combination of F1 and F2 vs F3 in the 2DF group. One dominant follicle and 2DF developed in 21 (66%) and 11 (34%) waves, respectively. Double ovulations occurred in only one of the waves with 2DF. In 8/11 waves with 2DF, a second deviation occurred between F1 and F2 on 2.5 +/- 0.4 days after the first deviation. On day 0, 1DF and 2DF waves were similar in number of days after ovulation, number of follicles, difference in diameter between F1 and F2, and plasma concentrations of LH, estradiol and immunoreactive inhibin. The interval from maximum FSH concentration to day 0 was longer (p < 0.05) and FSH concentration was lower (p < 0.05) on days -1 to 4 in the 2DF group. The similarities on day 0 in the characteristics of 1DF and 2DF waves despite the differences in the declining portions of the FSH profile indicated that a specific day of the FSH decline or a specific concentration were not factors in initiating deviation. Unlike reported results in heifers, the results in mares did not indicate a hormonal basis for the development of 2DF or two deviations.
Publication Date: 2008-10-18 PubMed ID: 18992111DOI: 10.1111/j.1439-0531.2007.01048.xGoogle Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The research examines the dynamics of follicle development in horse ovaries, specifically comparing situations when either one or two main follicles develop. It aimed to unravel any hormonal or other factors that may initiate these varying dynamics in follicle development.
Research Methodology
- The researchers studied the growth and hormonal characteristics of 32 ovulatory follicular waves in adult female horses (mares).
- The follicles were ranked according to size – the largest was designated as F1, the second largest as F2, and so on.
- The beginning of deviation, day 0, was defined as the day before the difference in diameter between F1 and F2 started to increase in cases where one dominant follicle developed (1DF), or between F1+F2 and F3 in cases where two dominant follicles developed (2DF).
Findings
- In 66% of the waves, one dominant follicle developed, while in 34% of them, two dominant follicles developed.
- Double ovulations were observed in only one of the 2DF wave occurrences.
- In the majority (8 out of 11) of 2DF wave occurrences, a second deviation in size between F1 and F2 was observed about 2.5 days after the first one.
Ovarian Hormone Profile
- The levels of LH (luteinizing hormone), estradiol, and inhibin in the blood samples taken on day 0 were similar for both 1DF and 2DF waves, as were the number of follicles and differences in diameter between the largest follicles.
- However, the time difference between when FSH (follicle-stimulating hormone) concentration was at its peak and day 0 was longer, and the FSH concentration was lower from one day before day 0 to four days afterwards in the 2DF group compared to the 1DF group.
Conclusions
- The researchers concluded that while some differences in follicle-stimulating hormone levels were seen with 1DF and 2DF waves, a specific stage of FSH decline or concentration did not necessarily trigger follicle deviation.
- Moreover, unlike previous studies on young female cows (heifers), they did not observe a clear hormonal basis for the formation of two dominant follicles or two deviations in mares.
Cite This Article
APA
Jacob JC, Gastal EL, Gastal MO, Carvalho GR, Beg MA, Ginther OJ.
(2008).
Follicle deviation in ovulatory follicular waves with one or two dominant follicles in mares.
Reprod Domest Anim, 44(2), 248-254.
https://doi.org/10.1111/j.1439-0531.2007.01048.x Publication
Researcher Affiliations
- Eutheria Foundation, Cross Plains, WI, USA.
MeSH Terms
- Animals
- Estradiol / blood
- Female
- Follicle Stimulating Hormone / blood
- Horses / physiology
- Inhibins / blood
- Luteinizing Hormone / blood
- Ovarian Follicle / anatomy & histology
- Ovarian Follicle / diagnostic imaging
- Ovarian Follicle / physiology
- Ovulation / physiology
- Ultrasonography
Citations
This article has been cited 1 times.- Vaiarelli A, Cimadomo D, Trabucco E, Vallefuoco R, Buffo L, Dusi L, Fiorini F, Barnocchi N, Bulletti FM, Rienzi L, Ubaldi FM. Double Stimulation in the Same Ovarian Cycle (DuoStim) to Maximize the Number of Oocytes Retrieved From Poor Prognosis Patients: A Multicenter Experience and SWOT Analysis.. Front Endocrinol (Lausanne) 2018;9:317.
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