Assessment of paternal effect and physiological cost of metamorphosis on growth of young winter flounder Pseudopleuronectes americanus juveniles in a cold environment

摘要

This study assessed the paternal effects on the growth of early juvenile winter flounder Pseudopleuronectes americanus and examined the energy allocation strategy employed during this critical stage. Males from three different locations (Passamaquoddy Bay, Baie-des-Chaleurs and the St Lawrence Estuary) were crossed with females from the Baie-des-Chaleurs, and the growth characteristics of hybrids from settlement to 45 days post-settlement were monitored under similar culture conditions. Young juveniles displayed good growth rates (0 center dot 09 +/- 0 center dot 02 mm day-1), with no differences related to sire origin, in terms of growth indicators (length, width, RNA:DNA and triacylglycerol:sterol ratios), condition indices (Fulton's K, pigmentation and fin erosion) and biochemical components (nucleic acids, proteins and lipid classes). These results suggest the absence of a paternal contribution to the growth strategy during the early juvenile stage of P. americanus. The results also highlight the high energetic cost associated with metamorphosis: young juveniles mobilized most of their triacylglycerol reserves during the growth period following settlement.