Ovary and egg fatty acid composition of greater amberjack broodstock (Seriola dumerili) fed different dietary fatty acids profiles

摘要

The aim of this study was to assess the effect of an experimental diet (ED), with high levels of 18:1 n-9 and low eicosapentaenoic to arachidonic acid ratio (EPA/AA), on the fatty acid (FA) profile of ovary and eggs of Seriola dumerili broodstock, in contrast to a non-specific commercial diet (nsCD), taking wild fish lipid composition as a positive reference. Two groups of Seriola broodstock born in captivity were fed with either the ED or the nsCD during two consecutive spawning seasons (21 months). After 7 months of feeding, fish fed the ED displayed an ovary FA profile much closer to wild fish. During the second spawning season, only the group fed ED released eggs. Egg FA composition showed some minor changes throughout the spawning season, with a marginal reduction of EPA in the late season being the most striking variation. Overall, the use of the ED showed some positive results, which could favor spontaneous egg release from females born in captivity. However, the lack of fertilization and the high level of 18:2 n-6 in the ovary tissue and eggs indicate that further improvements are needed in 5. dumerili broodstock diet formulation in order to enhance the reproductive performance of this species in captivity.