Evaluation of feeding performance of early siganid, Siganus guttatus, larvae fed with mixed zooplankton

Abstract

<i>Siganus guttatus</i> is an economically important rabbitfish for commercial farming. It is very important to evaluate their feeding performance particularly the effects of different diets for this larvae and to determine their growth and survival after being fed on different diets. Newly-hatched siganid, Siganus guttatus, larvae were reared in 500-L fiberglass tanks and fed either on copepod nauplii and rotifers alone or combination of both. Copepod nauplii proliferated in tanks consisted mainly of <i>Pseudodiaptomus</i> sp., and <i>Acartia</i> sp. Siganid larvae successfully commenced feeding (feeding incidence) on early stage copepod nauplii even if their abundance was low. Selective feeding ability of larvae seemed to start from day 6 and the larvae thereafter preferred to feed nauplii than rotifers. Survival of the siganid larvae was significantly higher when fed with with combination of rotifers and copepod nauplii compared to those fed with either rotifers or copepod alone. The growth of the larvae however are the same for all treatments. Results of this study suggest that coastal calanoid copepods of the genus <i>Pseudodiaptomus</i> sp. and <i>Acartia</i> sp. could be reproduced in tanks and their nauplii can be used as food for siganid larval rearing.