Lyophilized extender supplemented with rainbow trout (oncorhynchus mykiss) seminal plasma improves cryopreservation of ram sperm

Abstract

Th is study aimed to investigate the eff ect of the Rainbow trout seminal plasma (RTSP) supplemented (control, 10% or 15%) lyophilized extender on freezability of ram semen. Collected semen was pooled and split into two aliquots, and each of the ejaculates was diluted with fresh or lyophilized extenders with RTSP (0%, FC and LC; 10% F10 and L10or 15% F15 and L15) using two-step dilution method. Semen was frozen using the programmable freezing machine. Semen samples were examined for sperm motility, defective acrosomes, plasma membrane integrity and DNA fragmentation at native and post-thaw stage. Th e highest percentages of post-thaw motility and plasma integrity were observed in the F10, F15, and L15 (P0.05). Th e highest percentage of post-thaw DNA fragmentation values were observed in the FC group, while the lowest DNA fragmentation was obtained in the F15 but only significant diff erent from FC and LC groups. In conclusion, the findings of this study show that the lyophilized extender with 15% RTSP added can be used successfully for freezing ram semen.

Keywords

• cryopreservation
• lyophilized extender
• rainbow trout seminal plasma
• ram semen