Induction of gynogenesis by using inactivated heterologous sperm to produce male Sterlet sturgeon (Acipenser ruthenus)

Based on IUCN criteria, sterlet sturgeon (Acipenser ruthenus) has been shown as vulnerable species. Its male sex is inadequate or absent in the most of propagation and rehabilitation centers of Iran. The aim of this study is the induction of gynogenesis to produce male sterlet sturgeon using heterologous sperm. DNA of heterologous sperm from Siberian sturgeon (Acipenser baerii) was damaged successfully by UV irradiation with 473 µw/cm2 intensity and 90 seconds duration. The irradiated sperm mixed with sterlet sturgeon eggs to induce gynogenetic progenies of sterlet sturgeon. For this purpose, 15 minutes after activation, the fertilized eggs exposed to 34ºC heat shock for 2 minutes. Gynogenetic progenies were verified by microsatellite markers (AFU68 and AFUG195) as only maternal heritability. Histological observations of preliminary gonads of gynogenetic progenies were carried out by biopsy method at 17 months-age. Results showed that gynogenetic progenies consisted of 76.6% female and 23.3% male. Regarding to female heterogametic sex determination system in sterlet sturgeon, this study showed that both female and male as pure could be induced by inactivated heterologous sperm and gynogenesis.