Effect of dietary taurine enhancement on growth and development in red sea bream Pagrus major larvae

This study investigated the effect of feedings taurine-enriched rotifers on the growth and development of larval red sea bream (RSB). Rotifers incubated in taurine-enriched water at a taurine concentration of 800mgL(-1) (T-800) and 0mgL(-1) (T-0) were fed to larvae from 3 to 20days after hatching (DAH). Notochord length, body weight and specific growth rate of T-800 group were significantly greater than those of T-0 at 14, 17, 9-11 and 18-20 DAH. Taurine content of larvae in the T-800 group increased rapidly from 11 DAH and thereafter remained significantly higher than T-0. Flexion larvae firstly appeared in both groups at 8 DAH, however, at 20 DAH post-flexion larvae were significantly more abundant in T-800 than T-0. While nucleic acid and protein contents (gmg(-1) wet fish) showed remarkable changes, ontogenetic growth in RSB larvae stage was observed to switch from hyperplastic growth to hypertrophic growth with the start of the flexion stage. Although a similar change in nucleic acid contents was observed between the two groups, the protein content (gfish(-1)) and protein/DNA ratio of T-800 remained higher than that of T-0 during the hypertrophic growth period. These results suggest that dietary taurine accelerates the growth and development in RSB larvae especially during hypertrophic growth (flexion stage) after the early hyperplastic growth.