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Updated: Oct 29, 2025

Collection of Post-mating Semen from the Female Reproductive Tract and Measurement of Semen Liquefaction in Mice
Published on: November 18, 2017
Effect of different carboxylated poly l-lysine and dimethyl sulfoxide combinations on post thaw rabbit sperm
Niyazi Küçük1, Sanan Raza2, Kazuaki Matsumura3
1Department of Reproduction and Artificial Insemination, Faculty of Veterinary Medicine, University of Aydin Adnan Menderes, 09016 Aydın, Turkey.
Abstract:
Antifreeze proteins are biologically active substances which protect living organisms against freezing injuries. The effect of a synthetic antifreeze protein carboxylated poly l-lysine (CPLL) in the extender was evaluated in the presence of a conventional cryoprotective agent, dimethyl sulfoxide (Me2SO), for freezing rabbit sperm cells. The experiment was conducted according to 2 × 3 factorial design including two Me2SO (5 or 8%) and three CPLL (0, 0.5 or 1%) concentrations. CPLL supplementation improved post-thaw live and live-acrosome intact sperm rates (P<0.01) without a prominent influence on the motility (P>0.05) and live-membrane intact (P>0.05) sperm rates. The most striking effect of CPLL supplementation was seen on the DNA integrity where it reduced DNA fragmentation of sperm cells significantly by interacting Me2SO (P < 0.01) during freezing and thawing. However, it could not replace Me2SO in the extender and did not improve pregnancy rate. In conclusion, CPLL supplementation to the extender in the presence of Me2SO improved sperm quality parameters and post-thaw DNA integrity.

