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International Journal of Innovative Approaches in Agricultural Research 2026, Vol 10(1) 1-12

Effect of the Freezing Month and Breed on Post-Thaw Equine Semen Quality

Amel Najjar • Fatma Riahi • Sofiane Ezzar • Belgacem Benaoun
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Article Type
Research article
Publication Date
May 26, 2026
Pages
1-12
DOI
10.29329/ijiaar.2026.1423.6

Abstract

The quality of frozen-thawed semen in stallions is an important component of equine reproduction and can be influenced by various intrinsic and environmental factors. This study investigated the effects of stallion breed and freezing month on post-thaw semen quality. A total of 96 ejaculates were collected from Arabian, Arab-Barb, and French Saddle stallions and frozen between November 2023 and March 2024 using a stantardized cryopreservation protocol. Post-thaw semen quality was evaluated based on sperm motility, viability, morphology (head, midpiece, tail defects and cytoplasmic droplets), membrane integrity, and sperm head area. The freezing month significantly affected sperm motility and membrane integrity (P < 0.05), with the highest values recorded in January and March. Midpiece and tail defects, as well as cytoplasmic droplets, varied significantly across months (P < 0.05), whereas sperm viability and head area were not affected (P > 0.05). Breed had a significant influence on semen quality. Arab-Barb stallions showed lower sperm motility and higher rates of head and midpiece defects compared to Arabian and French Saddle stallions (P < 0.05). However, sperm viability and membrane integrity were not affected by breed (P > 0.05). In conclusion, both breed and freezing month influenced post-thaw semen quality. January appeared to be a particularly favorable period for semen cryopreservation. These findings highlight the importance of considering breed- and season-related factors when optimizing semen cryopreservation protocols to improve reproductive efficiency in stallions.

Keywords: Stallion Reproduction Semen Cryopreservation Post-Thaw Semen Quality Sperm Motility Sperm Morphology Stallions
Cite this article
Najjar, A., Riahi, F., Ezzar, S., & Benaoun, B. (2026). Effect of the Freezing Month and Breed on Post-Thaw Equine Semen Quality. International Journal of Innovative Approaches in Agricultural Research, 10(1), 1-12. https://doi.org/10.29329/ijiaar.2026.1423.6

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