Artificial Gynogenesis and Sex Reversalin Hypophthalmichthys molitrix

For gynogenesis experiments,spermatozoa from carp was exposed to UVirradiation to destroy genetic materials.Eggs from silver carp (Hypophthalmichthys molitrix)were fertilized'by irradiated spermatozoa which only play the role of stimulatingegg.Heat shock was applied for 3 min after fertilization in 41℃ to double the genomeploidy of the resulting haploid 'fertilized egg'.When the fish had reached 10cm in length,Silastic tube containing methyltestosterone was implanted into the fish body.Althoughthe gonad could develop to reach Phase I,the regression of gonad was observed in testgroups compared with controls,suggesting the hormone released from Silastie tube canaffect gonad development.