Dietary fatty acids affect female white bass (Morone chrysops) reproductive performance, progeny quality, and juvenile sunshine bass (Morone chrysops x Morone saxatilis) composition.

摘要

I evaluated the extent to which fatty acids of maternal origin influence reproductive performance of white bass Morone chrysops, egg fatty acids, and viability of progeny of sunshine bass [female symbol omitted] M. chrysops x [male symbol omitted]M. saxatilis fry up to first feeding. I also examined how fatty acids of "environmental" origin influence the fatty acid compositions of zooplankton and fingerling sunshine bass in earthen ponds. I found live foods are an effective feeding regime for female white bass broodstock compared to current commercial feed formulations, ensuring significantly (P≤0.05) elevated highly unsaturated fatty acids (HUFA) content within eggs as well as an associated higher hatchability. A subsequent experiment in which female white bass were fed varying levels of menhaden fish oil (0, 25, 75, 100% of dietary lipid) indicated the hatchability of their eggs was directly related to dietary n-HUFA and ARA. Eggs with higher hatchability were associated with significantly (P≤0.05) higher levels of n-3 HUFA, including eicosapentaenoic acid (20:5n-3; EPA), docosapentaenoic acid (22:5n-3; DPA), and DHA. My results also suggest white bass broodstock possess low and moderate regulatory control (preferential inclusion) to deposit neutral and polar fatty acid, respectfully, to the egg. I demonstrated the fatty acid composition of organic fertilizers significantly (P≤0.05) influence the fatty acid composition of pond-reared sunshine bass fingerlings and resident zooplankton. Juveniles reared in ponds fertilized with flaxseed possessed almost two-fold higher concentrations of 18:3n-3 compared to fingerlings reared in the cottonseed and rice bran treatments, which coincides with the higher levels of 18:3n-3 in flaxseed compared to the other aforementioned treatments. Similar significant (P≤0.05) differences existed among the treatments in the fatty acid composition of zooplankton. My research suggests white bass and their hybrids possess little to no capability of further elongation and desaturation as well as tissue inclusion of dietary C18 precursors. The information gathered through my work attempts to better understand the affects of dietary fatty acids on reproductive and developmental processes in Morone spp. Moreover, the information gathered in all studies provides a research foundation for improving the sustainability of viable eggs and fingerlings for the hybrid striped bass industry.