Influence of stocking density on tissue lipid composition in flatfish Scophthalmus rhombus

Abstract

The effects of the stocking density on the tissue lipid composition and biometric features of the brill were studied. Fish were cultured at three different stocking densities: 1; 5 and 15 Kg m-2 (LSD, MSD and HSD) during 5 weeks. Survival and several biometric, feeding and tissue lipid composition were assessed. Although final weight and specific growth rate decreased in higher densities, there were not significant differences between MSD and HSD. Differences for survival rate, feed efficiency, conversion index and feed intake were not detected among treatments. The minimum HSI was found in the HSD treatment, and condition factor varied inversely regards to stocking density. In liver, no differences among treatments were registered for total neutral lipids (TNL), though total polar lipids (TPL) was significantly higher in HSD. Muscle TPL did not vary significantly between LSD and HSD, but TNL was significantly higher in HSD. This work was supported by Interreg Project 0251_ECOAQUA_5_E, financed by the EDRF (European Regional Development Fund).www.juntadeandalucia.es/agriculturaypesca/ifapa/ecoaqua. Se analiz&oacute; el efecto de la densidad de cultivo de parrachos en la composici&oacute;n lip&iacute;dica de diferentes tejidos de esta especie, as&iacute; como en la supervivencia y varios par&aacute;metros biom&eacute;tricos. Los peces se cultivaron durante 5 semanas a 3 densidades de cultivo: 1; 5 and 15 Kg m-2 (LSD, MSD y HSD). El peso final y la tasa de crecimiento espec&iacute;fica fueron menores en los cultivos a m&aacute;s densidad. Sin embargo no se observaron diferencias entre los grupos en supervivencia, eficiencia alimentaria, &iacute;ndice de conversi&oacute;n y tasa de ingesti&oacute;n. El &iacute;ndice hepatosom&aacute;tico fue menor los peces cultivados a m&aacute;s densidad. En el h&iacute;gado no se detectaron diferencias en los l&iacute;pidos neutros totales (TNL) entre los tratamientos, aunque la cantidad de l&iacute;pidos polares totales (TPL) fue mayor en HSD. En cambio los TPL fueron similares en el m&uacute;sculo en todos los tratamientos, mientras que los TNL fueron significativamente mayores en los peces cultivados a m&aacute;s densidad (HSD). Este trabajo fue apoyado por el proyecto Interreg 0251_ECOAQUA_5_E , financiado por el FEDER (Fondo Europeo de Desarrollo Regional).www.juntadeandalucia.es/agriculturaypesca/ifapa/ecoaqua.</p