Ontogenetic Behavior and Phototactic Properties of Interspecific Hybrid Prolarvae Produced by Crossing Female Siberian Sturgeon Acipenser baerii and Male Russian Sturgeon Acipenser gueldenstaedtii

摘要

Female Siberian sturgeon Acipenser baerii were crossed with male Russian sturgeon A. gueldenstaedtii and the development, ontogenetic behavior, and phototactic characteristics of the resultant hybrid prolarvae were examined. The fertilization rate ofthe hybrid group was similar to that of Siberian sturgeon (the maternal species), and the overall developmental characteristics of hybrid embryos were not significantly different from those of either parental species. The time window from first hatch tothe completion of hatching was wider in Russian sturgeon than in Siberian and hybrid sturgeon groups. The prolarval viability of the hybrid group was similar to that of the maternal species, and significantly higher than that of the paternal species. Hybrid prolarvae displayed ontogenetic behavioral patterns that were quite similar to those of Siberian sturgeon. In an illumination preference test, hybrid prolarvae displayed significant positive phototaxis, similar to the maternal species, and clearly distinct from the negative phototactic character of the paternal species. Taken together, our data indicate that the prolarval traits of hybrid sturgeon from this cross more closely resemble those of the maternal than the paternal species.