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Published on: May 11, 2017
X trisomy in a sterile mare
L de Lorenzi1, L Molteni, M Zannotti
1Department of Animal Science, Milan University, Italy.
Equine Veterinary Journal
|July 20, 2010
Summary
This study analyzed a sterile mare using cytogenetic techniques, revealing a rare XXX condition. This finding suggests that X trisomy in horses can cause infertility without obvious physical traits.
Area of Science:
- Animal genetics
- Reproductive biology
- Cytogenetics
Background:
- Infertility in mares can have various causes, including genetic factors.
- Cytogenetic abnormalities, though rare, are potential contributors to reproductive failure in horses.
- Understanding the genetic basis of infertility is crucial for equine breeding programs.
Purpose of the Study:
- To investigate the cytogenetic profile of a reproductively unsuccessful mare.
- To determine if chromosomal abnormalities are associated with infertility in this specific case.
- To contribute to the understanding of genetic causes of equine infertility.
Main Methods:
- The study employed C-banding and fluorescence in situ hybridisation (FISH) for detailed chromosomal analysis.
- These techniques allowed for precise identification of chromosomal number and structure.
- The mare's cells were analyzed to detect any signs of mosaicism.
Main Results:
- The sterile mare was found to have a 2n = 65, XXX chromosomal condition.
- No evidence of chromosomal mosaicism was detected in the analyzed cells.
- The identified XXX condition represents a rare occurrence in the horse population.
Conclusions:
- The XXX condition, or X trisomy, is implicated as a cause of infertility in mares.
- This chromosomal abnormality does not appear to be linked to other discernible phenotypic characteristics.
- The findings support the hypothesis that X trisomy is a significant factor in equine infertility.
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