Ultra-low temperature cryopreservation and-80°C storage of sperm from normal-male and pseudo-male Siniperca chuatsi

The purpose of this study was to evaluate the effects of ultra-low temperature cryopreservation and -80 degrees C storage of sperm from normal-male and pseudo-male mandarin fish (Siniperca chuatsi). In this study, sperm motility, plasma membrane integrity, mitochondrial membrane integrity, DNA integrity, fertilization, hatching rate and offspring growth were evaluated. After thawing, there was no significant difference in sperm motility and motility parameters of stripped sperm and testicular sperm of normal-males and pseudo-males. The motility of frozen sperm thawed in a 37 degrees C water bath was the highest, and there was no significant difference in the motility of frozen sperm of different tubes (n = 30) after thawing. The motility of frozen sperm of normal-males and pseudo-males were more than 60%, and the DNA fragmentation were less than 10%. The integrity of mitochondria and plasma membrane were higher than 84% and 75% respectively. There were no significant differences in plasma membrane, mitochondrial membrane integrity and DNA fragmentation between fresh sperm of normal-males and pseudo-males, nor between frozen sperm. The fertilization and hatching rate of normal-male frozen sperm were 65% and 85%, and values of pseudo-male frozen sperm were 57% and 83%, respectively. There was no significant difference in the body weight and length of offspring of frozen sperm between the normal-males and pseudo-males. The sperm motility, motility parameters and mitochondrial membrane integrity of the frozen sperm of normal-males and pseudo-males did not significantly decrease after -80 degrees C storage for 1, 3 and 5 days. The fertilization and hatching rate of normal-male and pseudo-male frozen sperm were still higher than 50% and 75%. Frozen sperm can successfully reproduce offspring after 5 days of -80 degrees C storage. The results indicated that testicular sperm of normal-male and pseudo-male S. chuatsi were successfully cryopreserved by ultra-low temperature cryopreservation, and the research of -80 degrees C storage showed that frozen sperm can be successfully stored for a short time at -80 degrees C which can provide a possibility for the dry ice transportation of frozen sperm.

Automated summary

This study evaluated the effects of ultra-low temperature cryopreservation and -80 degrees C storage on sperm from mandarin fish. The results showed that thawed sperms maintained high motility and quality parameters. Storage at -80 degrees C did not significantly affect the sperm's viability and its ability to reproduce offspring.