Dietary effects of rotifers, brine shrimps and cultured copepods on survival and growth of newborn seahorse Hippocampus kuda (Bleeker 1852)

Aim : Low survival remains a significant obstacle during the early culture of Hippocampus kuda. To potentially develop a better feeding regime to newborn H. kuda without relying on wild zooplanktons, two separate feeding trialswere performed using cultured live food items. Methodology: Newborn H. kuda derived from the wild broodstock were reared in the captive conditions using different feeding regimes consisting of rotifers, Artemia and/or copepods Oithona simplex. The survival rate and growth performance were determined. Results : In the first experiment, despite consumption of both rotifers and Artemia, a total mortality was observed among seahorses on 3rd and 5th day-after-birth (DAB), when only rotifers or Artemia were provided, respectively. Seahorses fed the mixed live foods have 60% survival with 6.3% per day specific growth rate (SGR). In the second experiment, the introduction of copepods had further improved the SGR of H. kuda to 8.1% d'1 compared to 6.8% d'1 without copepods, although the survival was similar. Interpretation : Overall, the results indicated that in terms of survival, a feeding regime consisting of a rotifer and Artemia nauplii mixture was suitable for H. kuda juveniles during the first 10 days. To enhance growth, copepods O. simplex should be included in its diet since this live food was superior over enriched Artemia metanauplii. These findings are important to further develop an optimum feeding regime from reliable source of live foods for early culture of H. kuda.