Spatial distribution of preantral follicles in the equine ovary.
Abstract: Comprehensive studies on spatial distribution of preantral follicles in the ovary are scarce. Considering that preantral follicles represent the main ovarian reserve, harvesting of these follicles is crucial for the development/use of assisted reproductive techniques. Therefore, knowledge on follicle spatial distribution can be helpful for targeting areas with richer number of preantral follicles through biopsy procedures. The aim of this study was to assess the distribution and localization of equine preantral follicles according to: (i) age, (ii) ovarian portion (lateral and intermediary) and region (dorsal and ventral), (iii) distance from the geometric center, and (iv) follicular class. Ovaries from young and old mares (n = 8) were harvested in a slaughterhouse and submitted to histological processing for further evaluation. For data analyses, a novel methodology was developed according to the geometric center of each histological section for a precise determination of preantral follicle distribution. Results indicated that (i) equine preantral follicles are clustered and located near to the ovarian geometric center, and that aging induced their dispersion through the ovarian cortex; (ii) the distance from the geometric center was shorter for developing follicles than primordial; and (iii) secondary follicles were more distant from the geometric center but closer to the ovulation fossa. In conclusion, the spatial distribution of preantral follicles was successfully determined in the equine ovary and was affected by age, region, and portion.
Publication Date: 2018-06-13 PubMed ID: 29897931PubMed Central: PMC5999074DOI: 10.1371/journal.pone.0198108Google Scholar: Lookup
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- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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The study examines the arrangement and location of early-stage follicles within a horse’s ovary, a factor essential for medical procedures like biopsies. It shows that these follicles are grouped together and are usually found near the ovary’s geometric center. The follicle’s placement, distance from the ovary’s center, and aging’s impact on follicle positioning are crucial findings.
Objective of the Study
- The study targeted to understand the spatial distribution and localization of preantral follicles within the horse’s ovary. Information about the location of these follicles could greatly impact the efficacy of assisted reproductive techniques and harvesting procedures.
Research Methodology
- Horse ovaries from both young and old mares were harvested in a slaughterhouse and submitted for histological processing for further examination.
- To accurately determine the preantral follicle distribution, the researchers developed a new methodology based on the geometric center of each histological section.
Key Findings
- The research found that the equine preantral follicles are grouped and located close to the geometric center of the ovary. Moreover, as the horses aged, these follicles spread further into the ovarian cortex.
- The distance from the geometric center was found to be shorter for developing follicles than primordial ones. Secondary follicles, on the other hand, were found to be more distant from the geometric center but closer to the ovulation fossa.
Conclusion
- The study successfully determined the spatial distribution of preantral follicles in the horse’s ovary, which was discovered to be influenced by factors such as age, region, and portion of the ovary.
Cite This Article
APA
Alves BG, Alves KA, Gastal GDA, Gastal MO, Figueiredo JR, Gastal EL.
(2018).
Spatial distribution of preantral follicles in the equine ovary.
PLoS One, 13(6), e0198108.
https://doi.org/10.1371/journal.pone.0198108 Publication
Researcher Affiliations
- Department of Animal Science, Food and Nutrition, Southern Illinois University, Carbondale, Illinois, United States of America.
- Department of Animal Science, Food and Nutrition, Southern Illinois University, Carbondale, Illinois, United States of America.
- Department of Animal Science, Food and Nutrition, Southern Illinois University, Carbondale, Illinois, United States of America.
- Department of Animal Science, Food and Nutrition, Southern Illinois University, Carbondale, Illinois, United States of America.
- Laboratory of Manipulation of Oocytes and Preantral Follicles (LAMOFOPA), State University of Ceará, Fortaleza, CE, Brazil.
- Department of Animal Science, Food and Nutrition, Southern Illinois University, Carbondale, Illinois, United States of America.
MeSH Terms
- Age Factors
- Animals
- Cell Count
- Female
- Histological Techniques
- Horses / physiology
- Ovarian Follicle / cytology
- Ovarian Reserve / physiology
- Ovary / cytology
- Ovulation / physiology
Conflict of Interest Statement
The authors have declared that no competing interests exist.
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Citations
This article has been cited 3 times.- Hyde KA, Aguiar FLN, Alvarenga PB, Rezende AL, Alves BG, Alves KA, Gastal GDA, Gastal MO, Gastal EL. Characterization of preantral follicle clustering and neighborhood patterns in the equine ovary. PLoS One 2022;17(10):e0275396.
- Hyde KA, Aguiar FLN, Alves BG, Alves KA, Gastal GDA, Gastal MO, Gastal EL. Preantral follicle population and distribution in the horse ovary. Reprod Fertil 2022 Apr 1;3(2):90-102.
- Souza SS, Alves BG, Alves KA, Brandão FAS, Brito DCC, Gastal MO, Rodrigues APR, Figueireod JR, Teixeira DIA, Gastal EL. Heterotopic autotransplantation of ovarian tissue in a large animal model: Effects of cooling and VEGF. PLoS One 2020;15(11):e0241442.
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