Cryopreservation of carp spermatozoa by different extenders

Production and storage of the best gametes are practices undertaken by fishery managers and researchers to improve fish reproduction technology and obtain the best spawners. The male spawners of carp (Cyprinus carpio) were chosen from two warm-water fish hatcheries near Rasht, Guilan Province. For the study, duration of motility of sperms, sperm density and fertilization rate were considered. The best samples were chosen for mropreservation with four different extenders and were checked by fertilization tests after seven days of preservation in liquid nitrogen. Results showed that by 1:1 dilution rate, the Alsever solution had the best results. The fertilization rate, production of eyed ego and larvae by this extender in a multistage cooling experiment were 45r, 47.81" and 22.63 respectively