Egg production and larval rearing of orange-spotted grouper (Epinephelus coioides) using reared broodstocks in Hormozgan Province , Iran

Egg production of cultivated broodstocks of orange-spotted grouper, Epinephelus coioides and larvae rearing were surveyed in Iran from ۲۰۰۸ to ۲۰۱۲. . Broodstocks were obtained by rearing of ۷ wild juveniles (۵۸۷.۵۷ ± ۱۳۲.۶۳ g body weight) which were caught from the north of Persian Gulf in October ۲۰۰۸ and reared to December ۲۰۱۲.. Captured juvenile fishes were fed using defrosted trash fish at a rate of ۴-۶ percent of body weight per day.. Four-year-old fishes spawned spontaneously, when average weight of females and males were about ۷۰۲۰ ± ۱۲۷۷ g and ۵۱۲۸ ± ۲۵۳g respectively. Effects of four temperature ranges (۲۳-۲۴, ۲۶-۲۷, ۲۸-۲۹ and ۳۱-۳۲ °C ) and three tank size ( ۴۰L, ۳۰۰L and ۲۴۰۰L) on hatching and survivle rates were examined. Eggs were stocked as a density of ۲۵ Eggs L-۱. Effects of tank size on hatching rate and survival of larvae were assessed at ۱, ۵, ۱۰, ۲۰ and ۳۰ days after hatching (DAH).  The optimal temperature range for hatching was ۲۸-۲۹ °C. No difference was observed among hatching rates of fish within the various tank sizes. Survival rates of larvae in ۲۴۰۰L fiber glass tanks until ۳۰ days after hatching were significantly higher than the other tanks. Results indicate this species can be reproduced and reared in large numbers under normal rearing conditions and carefully controlled temperature.

Keywords:

Orange-spotted grouper , Eggs production , Larvae rearing , Epinephelus coioides , Tank size