earticle

영어

Conventional semen extenders contained egg yolk as cryoprotectant. However, egg yolk is an animal protein and has a risk of zoonotic disease such as influeza virus. Thus, the demand of other chemically defined substitutes is required. As substitutes of egg yolk, liposomes are used in semen extenders. The structure of liposomes is already defined and manufacturing of liposome is possible. However, there are few reports of field trial on liposome based semen extender. Thus, we examined the effect of a liposome-based extender (Optixcell) on frozen- thawed spermatozoa characteristics and calving rate. Tris-citric egg-yolk extender (Triladyl) used as a control. Motility, motility parameters, plasma membrane integrity, acrosomal membrane integrity of spermatozoa and calving rate were compared. Percentages of total motile spermatozoa were similar in the Optixcell and Triladyl groups. However, among motile spermatozoa with straight line velocity (VSL) ≥ 25 μm/sec, the curvilinear velocity (VCL, μm/sec), VSL (μm/sec), average path velocity (VAP, μm/sec), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), and plasma membrane integrity of frozen-thawed spermatozoa of the Optixcell group were significantly higher than those of the Triladyl group. Furthermore, calving rate in the Optixcell group (79.0%) was higher than that of the Triladyl group (62.8%). However, acrosomal membrane integrity of frozen-thawed spermatozoa in the Optixcell and Triladyl groups was similar. These results indicate that semen freezing with Optixcell improved motility and plasma membrane integrity of frozen-thawed spermatozoa and calving rate of Hanwoo cows (native Korean cattle). In conclusion, our results suggest that semen freezing with the liposome-based extender Optixcell is more efficient than the tris-citric egg-yolk extender Triladyl for improvement of offspring production.