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On the basis of IUCN criteria, Siberian sturgeon (Acipenser baerii) has been assorted as endangered (EN) species. The aim of this study was induction of female sex Siberian sturgeon using heterologous sperm and gynogenesis. DNA of heterologous sperm from Persian sturgeon (Acipenser persicus) was damaged by UV irradiation with 473 µw/cm2 intensity at 60, 120 and 180 sec durations with preserving of sperm motility to fertilize the eggs. On the basis of motility, fertilization and hatching rates, the best duration of exposed sperm under UV-irradiation was 180 seconds (8514 J/m2). After this duration, assessments showed sperm motility percentage as 40%, fertilization rate of haploid eggs as 52.1% and hatching rate of haploid eggs as 1.1%. These characteristics were recognized as: 70%, 70.7%, 65.5%, respectively in control treatment. UV-irradiated sperm mixed with Siberian sturgeon eggs. Then, the activated eggs exposed to 2ºC cold shock for 30 minutes, 10 minutes after activation to induce gynogenetic diploid of Siberian sturgeon. In this situation, fertilization and hatching rates increased to 59.5% and 41.6%, respectively which showed standard method for cold shock effect on diploidization of haploid progenies and successful induction of gynogenesis. Gynogenetic progenies were verified by microsatellite markers (Afu68, Afug9, Afug63, Afug112, Afug122 and Afug195) as only maternal heritability. In this study, phenotypic characteristics (morphometric and meristic) of hybrid treatment between female Siberian sturgeon and male Persian sturgeon showed a high resemblance between progenies and their paternal brood. So, if some spermatozoa failed to be UV-irradiated, the gynogenetic and other produced samples could be easily detectable. Meanwhile, biotechnique of inactivation of Persian sturgeon sperm along with gynogenesis induction could inhibit the danger of extinction of other sturgeon species.Key words: Siberian sturgeon, Persian sturgeon, gynogenesis, heterologous sperm.
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