TY - JOUR
T1 - Ultra-rapid freezing in spheres yields a higher cryoresistance than in straws but remains inferior to conventional slow freezing of stallion sperm
AU - Larriva-González, Francisco
AU - Erráez-Guaicha, Jefferson E.
AU - Torres-Ordóñez, Karen E.
AU - Duma, Mauricio
AU - Larriva-Salazar, Sebastián
AU - Galarza, Diego A.
N1 - Publisher Copyright:
© 2025 Society for Cryobiology
PY - 2025/9/8
Y1 - 2025/9/8
N2 - This study evaluated the cryoresistance of stallion sperm frozen by ultra-rapid (UR) methods using microspheres and straws or by the conventionally-slow (CS) method. Sixteen ejaculates from four stallions were each divided into three aliquots according to the freezing method: UR freezing in 30-μL spheres (UR-Spheres) by direct immersion in liquid nitrogen (LN2); UR freezing in 0.25-mL straws (UR-Straws) by direct horizontal submersion in LN2; and CS freezing in LN2 vapors. Ultra-rapid freezing medium included 100 mM trehalose +1 % BSA, and the CS freezing medium contained 5 % dimethylformamide. Conventional-slow freezing yielded higher sperm cryoresistance than both UR freezing methods (P < 0.05). UR-Spheres produced higher values of sperm kinematic, viability, and acrosomal integrity than UR-Straws (P < 0.05). Sperm head area and perimeter in both UR freezing groups increased compared to fresh and CS frozen samples (P < 0.05). In conclusion, the UR-Spheres method produced greater cryoresistance of stallion semen than UR-Straw method.
AB - This study evaluated the cryoresistance of stallion sperm frozen by ultra-rapid (UR) methods using microspheres and straws or by the conventionally-slow (CS) method. Sixteen ejaculates from four stallions were each divided into three aliquots according to the freezing method: UR freezing in 30-μL spheres (UR-Spheres) by direct immersion in liquid nitrogen (LN2); UR freezing in 0.25-mL straws (UR-Straws) by direct horizontal submersion in LN2; and CS freezing in LN2 vapors. Ultra-rapid freezing medium included 100 mM trehalose +1 % BSA, and the CS freezing medium contained 5 % dimethylformamide. Conventional-slow freezing yielded higher sperm cryoresistance than both UR freezing methods (P < 0.05). UR-Spheres produced higher values of sperm kinematic, viability, and acrosomal integrity than UR-Straws (P < 0.05). Sperm head area and perimeter in both UR freezing groups increased compared to fresh and CS frozen samples (P < 0.05). In conclusion, the UR-Spheres method produced greater cryoresistance of stallion semen than UR-Straw method.
KW - Spheres
KW - Stallion sperm
KW - Straws
KW - Ultra-rapid freezing
KW - Stallion sperm
KW - Ultra-rapid freezing
KW - Spheres
KW - Straws
UR - https://www.scopus.com/pages/publications/105015092285
UR - https://www.mendeley.com/catalogue/483d08a4-442f-331b-8f8e-99c57f333275/
U2 - 10.1016/j.cryobiol.2025.105303
DO - 10.1016/j.cryobiol.2025.105303
M3 - Artículo
AN - SCOPUS:105015092285
SN - 0011-2240
VL - 121
JO - Cryobiology
JF - Cryobiology
M1 - 105303
ER -