Efficacy of Apocyclops royi (Cyclopoida, Copepoda) Nauplii as Live Prey for the First Feeding Larvae of Silver Pompano, Trachinotus blochii (Lacepède, 1801)

In the rearing of first exogenous feeding, marine finfish larvae availability of live prey with suitable size and nutritive content is vital for their growth and survival. Copepods represent an important alternative food to present traditional live feed organisms used in marine fish hatcheries. Use of copepods is known to improve survival, growth, and development of fish larvae. The silver pompano, Trachinotus blochii (Lacepède, 1801) is one of the suitable candidate species for aquaculture due to its fast growth, good meat quality and high market demand. The present study aimed to investigate the efficacy of Apocyclops royi nauplii in the rearing of first feeding larvae of T. blochii. The feeding experiments were conducted from 3 to 7 Day Post Hatch (DPH) using A. royi nauplii and Brachionus plicatilis (s type) diets. Higher growth of T. blochii larvae was evident with A. royi nauplii than that of rotifer diet. The A. royi nauplii fed experimental group of T. blochii larvae showed significantly different length (p <0.05) compared to rotifer fed larvae and the specific growth rate recorded was 29.42% and 24.28% in A. royi and rotifers fed experimental groups, respectively. On 7 DPH, A. royi nauplii fed T. blochii larvae showed higher mortality than rotifer fed group. With A. royi feed T. blochii larvae produced higher pigmentation which gradually started on the head and dorsal surface of the body from 3 DPH onwards and spread all over the body and became intense as the larvae grew to 7 DPH. Our results suggest the A. royi nauplii are suitable live prey for the T. blochii larvae during the initial feeding phase for better growth and pigmentation.