Attempts to induce gynogenetic chinook salmon by chinook‐sockeye and chinook‐brown trout crosses

Abstract

Attempts were made to induce gynogenesis in bisexual chinook salmon (Oncorhynchus tshawytscha) by insemination of chinook eggs with sperms from either sockeye salmon (O. nerka) or brown trout (Salmo trutta). In both crosses the success rate of induction of embryonic development was low and the hatched fish had poor survival. Physically normal and deformed progeny were found in both crosses. Our study suggests that the timing of pressure shock after insemination, and the method of application of pressure shock, may be critical in the induction of embryonic development. Electrophoretic analysis of soluble proteins and three isozymes revealed that the progeny produced by the two crosses were not truely gynogenetic, as paternal gene expression was detected. However, the persistent expression or non‐expression of the same paternal genes in all the progeny suggests that the activation or inactivation of these paternal genes did not occur at random.

Keywords:

• gynogenesis
• chinook
• sockeye
• brown trout
• pressure shock
• electrophoresis
• protein
• isozymes