| Popis: |
A population of European oysters (Ostrea edulis) was recently discovered off the eastern coast of Canada. The occurrence of this newly established population led various aquaculture stakeholders to consider this species commercially. To better assess recruitment capacity, the physiological quality of the adults, eggs, and larvae was described using glycogen and various lipid contents, including a TAG/ST ratio. Adults, early nonfeeding stages (eggs, pretrochophores, trochophores, veligers) and newly-released larvae were periodically sampled in the wild and/or the hatchery during the spawning period. The initial glycogen content was higher in wild oysters than hatchery-conditioned ones. The following larval stages showed higher lipid content in wild individuals as well. Spat collection in the wild was abundant. The free-living larvae, however, did not survive more than 10 days in the hatchery. TAG/ST ratios decreased during the veliger stage development and were lower when larvae were released from the paleal cavity of the female. The high spat collection observed in the wild suggests that observed TAG/ST ratios in early nonfeeding larvae are representative of a good larval quality. The physiological quality of the larvae in the wild seems to be good enough to allow larvae to settle in this particular environment. |
