Triploidy induction in shellfish aims to obtain faster growth and sterility of reared individuals. Triploid Pacific
oysters are most often not totally sterile, but have greatly reduced reproductive capacities compared to those
recorded in diploid individuals. The description of gamete output in triploid aquatic animals is most often
confined to the assessment of fecundity in females. The present work aims at further describing gamete quality
of triploid Pacific oysters and comparing it to values observed in diploid individuals. Diploid and triploid oysters
(produced bymating tetraploidmales ×diploid females) were reared in standard conditions and then transferred to
the wild to allow the offspring to attain reproductive maturity. At the end of gametogenesis, the reproductive
characteristics of both groups were estimated.