Improving the larval performance of greater amberjack (Seriola dumerili) during the weaning phase with taurine supplementation on dry diets

Abstract

Taurine has been identified as a required nutrient in several Seriola species, whereas optimum dietary taurine (Tau) levels during the weaning period have not been yet determined in greater amberjack. Therefore, the effect of dietary Tau in microdiets for larval greater amberjack was determined by feeding 30 days post-hatching (dph) larvae with four microdiets containing 0.32 to 4.16% Tau levels for 2 weeks. Growth, survival, histology, skeletal anomalies, and expression of growth and stress-related genes were studied. Total length, weight gain, and daily weight gain of the larvae fed 1.39% Tau were higher than those of fish fed the other Tau levels. No differences were found in the larval health parameters studied, including intestinal integrity. Nevertheless, greater amberjack larvae fed 0.32 and 4.16% Tau showed a higher incidence of total severe skeletal anomalies. Moreover, dietary Tau increase up to 1.39% led to the upregulation of certain growth and stress-related genes (gh, igf2, and trh). These findings denote the importance of Tau levels in weaning diets to promote growth, cope with stress, and enhance bone health in larval greater amberjack, suggesting optimum levels around 1.39% Tau on a dry basis of diet.