Enhanced survival in striped bass fingerlings after maternal triiodothyronine treatment

Elevation of the triiodothyronine (T₃) content of striped bass (Morone saxatilis) eggs by maternal T₃ injection confirms the uptake of T₃ by oocytes. The resulting offspring were influenced favorably by the T₃, as seen in quantitative indices of development. As reported previously, larvae from T₃-supplemented eggs raised under laboratory conditions exhibited increased body area, length, dry weight, and rates of swimbladder inflation and survival, compared to controls. Also, the T₃ content of unfertilized oocytes correlated positively and highly significantly with survival to two weeks of age within individual cohorts (Brownet al., 1988). In the present study, the survival of experimental and control striped bass was monitored through the fingerling stage, under hatchery production conditions. The rate of recovery of maternally T₃-treated cohorts from pond-culture was approximately fourfold that of controls. The striking effects of T₃ enrichment of eggs on offspring indicate the potential contribution of maternal hormones in striped bass development, and suggest possible applications in aquaculture.