Life history traits influence in gonad composition of two sympatric species of flatfish

Paralichthys orbignyanus and Paralichthys patagonicus are flatfish with different life history traits, having in common the condition of breeding in seawater. Paralichthys patagonicus remain their whole life in open seawater and Paralichthys orbignyanus are sometimes found in brackish water bodies. As marine and estuarine food webs have different fatty acid (FA) compositions, the aim of this study was to characterize the gonadal maturation of P. orbignyanus and P. patagonicus females through the analysis of lipid content and FA profile in order to understand to what extent life history traits are reflected in the ovarian composition. During gonadal maturation lipid content increased and FA profiles changed in both species, but the lipid increase was greater in P. orbignyanus. The N-3FA and n-3HUFA proportions increased in both species but were higher in P. orbignyanus. The differences between the lifestyles of these species were reflected in the ovarian FA profile mainly as a result of differences in their FA metabolism, causing a greater accumulation of n-3FA and n-3HUFA in P. orbignyanus than in P. patagonicus. The higher lipid accumulation in P. orbignyanus’ ovaries could indicate that this species, feeding in brackish water bodies, has the possibility of storing more energy than P. patagonicus.Paralichthys patagonicus e Paralichthys orbignyanusapresentam diferentes atributos nas suas histórias de vida, embora ambas se reproduzam no mar. Paralichthys patagonicus permanece toda a vida em águas abertas, enquanto P. orbignyanus é comumente encontrado em corpos de água salobra. Considerando que redes alimentares marinhas e estuarinas têm diferente composição de ácidos graxos (FA), o objetivo deste estudo foi caracterizar a maturação gonadal de fêmeas de P. orbignyanus e P. patagonicus analisando o conteúdo lipídico e perfil FA, a fim de estabelecer se as diferenças nas histórias de vida são refletidas na composição do ovário. Durante a maturação gonadal, em ambas as espécies, houve aumento do teor lipídico e o perfil FA mudou, mas o incremento foi maior em orbignyanus. As proporções de N-3FA e n-3HUFA aumentaram em ambas as espécies, mas foram maiores em P. orbignyanus. As diferenças entre os estilos de vida destas espécies foram refletidas no perfil de FA dos ovários, principalmente como resultado das diferenças no metabolismo de FA, causando maior acúmulo de n-3FA e n-3HUFA em P. orbignyanus. O maior acúmulo de lipídios nos ovários de P. orbignyanus poderia indicar que esta espécie, ao se alimentar em águas salobras, tem a possibilidade de armazenar mais energia do que P. patagonicus

Life history traits influence in gonad composition of two sympatric species of flatfish

AbstractParalichthys orbignyanus and Paralichthys patagonicus are flatfish with different life history traits, having in common the condition of breeding in seawater. Paralichthys patagonicus remain their whole life in open seawater and Paralichthys orbignyanus are sometimes found in brackish water bodies. As marine and estuarine food webs have different fatty acid (FA) compositions, the aim of this study was to characterize the gonadal maturation of P. orbignyanus and P. patagonicus females through the analysis of lipid content and FA profile in order to understand to what extent life history traits are reflected in the ovarian composition. During gonadal maturation lipid content increased and FA profiles changed in both species, but the lipid increase was greater in P. orbignyanus. The N-3FA and n-3HUFA proportions increased in both species but were higher in P. orbignyanus. The differences between the lifestyles of these species were reflected in the ovarian FA profile mainly as a result of differences in their FA metabolism, causing a greater accumulation of n-3FA and n-3HUFA in P. orbignyanus than in P. patagonicus. The higher lipid accumulation in P. orbignyanus’ ovaries could indicate that this species, feeding in brackish water bodies, has the possibility of storing more energy than P. patagonicus