Concentrations of follicle stimulating hormone associated with follicle selection, number of follicles, and ipsilateral vs contralateral relationships in mares.
Abstract: Diameter deviation or follicle selection during a follicular wave begins with continuous growth rate of F1 (dominant or selected follicle; DF) and decreasing growth rate of F2 (largest subordinate). Intraovarian patterns based on presence or absence of the DF and CL are DF-CL, DF, CL, and devoid (neither DF nor CL). The DF and CL relationships in a pair of ovaries are ipsilateral (DF-CL pattern and devoid pattern) and contralateral (DF pattern and CL pattern). The effects of patterns and relationships on F1, F2, and FSH during deviation were determined in 21 mares. Diameters of F1 and F2 at expected beginning of deviation (F1, 22.5 mm; day 0) defined deviation classifications of conventional (F2 ≥ 18.5 mm on day 0), F2-undersized (F2 < 18.5 mm), and F1,F2-switched (F2 larger than F1 on day -1 or 0). During the decline in the FSH surge, an interaction (P < 0.001) of deviation classification and day indicated that FSH concentration was greater (P < 0.05) in undersized than in conventional deviations on days -3 and -1 and intermediate in switched deviation. Low FSH during days -3 to -1 in switched deviation began to increase on day -1 during switching in diameter rank between F1 and F2. The number of subordinate follicles per wave that attained a maximum of 11 to <16 mm was greatest in the DF-CL and devoid patterns and in ipsilateral (4.2 ± 0.5 follicles) than in contralateral (2.5 ± 0.7) relationships (P < 0.03). Concentration of FSH was greater (P < 0.04) on days -4 to 5 in ipsilateral (5.3 ± 0.2 ng/mL) than in contralateral (4.2 ± 0.4 ng/mL) relationships consistent with more follicles 11 to < 16 mm. In a survey (N = 63), an ipsilateral vs contralateral relationship was associated with 17 vs 17 conventional deviations and 7 vs 22 nonconventional deviations (P < 0.04), and conventional deviation (54%) was more frequent (P < 0.0001) than undersized (21%) or switched (25%) deviations. Results supported the hypotheses that (1) diameter deviation can be classified in mares into distinct categories based on diameter and rank of the future largest subordinate at expected deviation, (2) the number of subordinate follicles is influenced by ipsilateral vs contralateral relationships of DF and CL, and (3) conventional deviation is more common when the relationship between DF and CL is ipsilateral. Knowledge on follicle diameters for the different deviation classifications should be considered in studying follicle selection especially when terminal follicle sampling is done before expected deviation.
Copyright © 2018 Elsevier Inc. All rights reserved.
Publication Date: 2018-02-24 PubMed ID: 29544123DOI: 10.1016/j.theriogenology.2018.02.017Google Scholar: Lookup
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- Journal Article
Summary
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This research examines the relationship between follicle-stimulating hormone (FSH) levels, follicle selection, and the occurrence of ipsilateral vs contralateral relationships in ovary pairs in mares. The study finds that these relationships and the size of the follicles at a particular time can determine the pattern of follicle growth and selection.
Objective of the Research
- The primary aim of this study was to examine how patterns and relationships between dominant follicles (DF), subordinate follicles (F2), and the FSH hormone during follicle deviation in mares. Follicle deviation refers to the process during a follicular wave where a dominant or selected follicle (F1) continues to grow at a steady rate, while the growth rate of the next largest subordinate follicle (F2) decreases.
Study Design
- The study involved 21 mares and focused on deviation classifications based on F1 and F2 diameters at the expected beginning of deviation. Deviation was classified into conventional, F2-undersized, and F1,F2-switched.
- Research analysis was conducted to understand if and how deviation classification and day affect FSH concentration during the decline of the FSH surge.
Key Findings
- The researchers found that FSH concentration was superior in undersized deviations on certain days and intermediate in switched deviations. Whilst low FSH during specific days in switched deviation began to rise on the day F1 and F2 switched in diameter rank.
- The study revealed a significant correlation between the number of subordinate follicles per wave and the patterns and relationships of DF and CL. Specifically, more follicles were found in the DF-CL and devoid patterns and in ipsilateral relationships than in contralateral relationships.
- Concentration of FSH was found to be higher on certain days in ipsilateral relationships than in contralateral ones, suggesting the presence of more follicles of a certain size.
- An additional survey showed that conventional deviation was more common when DF and CL shared an ipsilateral relationship.
Research Implications
- The findings provide insights into how diameter deviation can be classified in mares into distinct categories based on the size and rank of the future largest subordinate at the expected deviation.
- The results may have significant implications in studies of follicle selection, particularly when terminal follicle sampling is conducted before expected deviation.
Cite This Article
APA
Ginther OJ, Domingues RR, Dangudubiyyam SV, Araujo ER.
(2018).
Concentrations of follicle stimulating hormone associated with follicle selection, number of follicles, and ipsilateral vs contralateral relationships in mares.
Theriogenology, 113, 159-165.
https://doi.org/10.1016/j.theriogenology.2018.02.017 Publication
Researcher Affiliations
- Eutheria Foundation, Cross Plains, WI 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA. Electronic address: oj.ginther@wisc.edu.
- Eutheria Foundation, Cross Plains, WI 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA.
- Eutheria Foundation, Cross Plains, WI 53528, USA.
- Eutheria Foundation, Cross Plains, WI 53528, USA; Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706, USA.
MeSH Terms
- Animals
- Female
- Follicle Stimulating Hormone / blood
- Follicle Stimulating Hormone / metabolism
- Horses / physiology
- Ovarian Follicle / physiology
- Ovulation / physiology
Citations
This article has been cited 1 times.- Liu Q, Zhang J, Wen H, Feng Y, Zhang X, Xiang H, Cao Y, Tong X, Ji Y, Xue Z. Analyzing the Transcriptome Profile of Human Cumulus Cells Related to Embryo Quality via RNA Sequencing. Biomed Res Int 2018;2018:9846274.
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