Gonadal histology and concentration of 11-ketotesterone of meiotic gynogens confirm female heterogametic sex determination in sterlet (Acipenser ruthenus)

Gynogenetic progeny of sterlet Acipenser ruthenus were obtained by inseminating eggs with UV-inactivated sperm followed by meiotic restoration of ploidy by heat shock. Gynogenetic origin of progeny was assessed by parentage assignment using 15 microsatellite markers. Sex ratio was investigated by gonad histology in 15 3-year-old fish, eight of which were confirmed gynogenotes, with five of those containing primary oocytes (62.5%). Blood plasma concentration of 11-ketotestosterone (KT-11) was analyzed in 63 4-year-old juveniles, 46 of which were genetically confirmed gynogenotes. Measurement of KT-11 showed the proportion of female sterlet to be 65.2%. This sex ratio conformed to the current hypothesis of female heterogametic sex determination but was at the low end of the reported female ratio in sturgeon gynogenetic progeny.

Automated summary

Gynogenetic progeny of sterlet Acipenser ruthenus were obtained by inseminating eggs with UV-inactivated sperm followed by meiotic restoration of ploidy by heat shock. The sex ratio of female sterlet was found to be 65.2%, which is in line with the current hypothesis of female heterogametic sex determination but lower than the reported female ratio in sturgeon gynogenetic progeny.