Comparative Sudy on the Use of Two Commercial Diets for Grow-out of Golden Rabbitfish, Siganus guttatus Reared in Sea Cages
Agus Nawang(a*), Ramadhan (b), Rosni (c), SRH Mulyaningrum(a), Lideman(a), MC Undu(d), Muhamad Safri(a), Syaiful Ardyansya(a), Tuti Asriani(c), Asda Laining(a)

a. Research Center for Fishery, National Research and Innovation Agency, Cibinong, Bogor, Indonesia
b Research Institute for Coastal Aquaculture and Fisheries Extension (RICAFE), Ministry of Marine Affairs and Fisheries, Maros 90512, South Sulawesi, Indonesia
c. Research Center for Conservation of Marine and Inland Water Resources, National Research and Innovation Agency, Cibinong, Bogor, Indonesia
d. Polytechnic of Marine and Fisheries of Jembrana, Ministry of Marine Affairs and Fisheries, Jembrana, Bali, Indonesia

Abstract

A 2x2x2 Factorial design was arranged to evaluate the effects of two factors which were commercial diet containing different protein levels of 22 and 26%, respectively and weight of golden rabbitfish (small and big) of S.guttatus on growth, feed utilization and proximate content of fillet when reared in floating sea cages. The feeding trial used 8 cages of 2x2x2 m3 stocked with 50 fishes per cage. All cages were fed twice a day to satiation. Monitoring growth was conducted by monthly sampling. After 90 days, survival rate ranged from 90.8 to 97% and no significant differences among all groups. The growth response indicated by weight gain (WG) and specific growth rate (SGR) demonstrated similar trend that only fish weight significanty affected the growth and no interaction effect between type of commercial diet and weight of fish were detected on this parameter. Feed intake was not affected either types of commercial diet or weight of rabbitfish. In contrast, feed concersion rasio (FRC) was significantly influenced by weight of fish, but not affected by types of feed used. Moreover, interaction between two factors was sifnificantly detected on FCR. Lipid content in fillet was significantly affected by the type of diet used and higher in the big fish when fed with diet contain 26% protein level. In conclusion, small fish grew faster than big fish and types of diet had similar effect on two size weights of fish groups. Small fish had better FCR when fed with diet containing 26% crude protein.

Keywords: Commercial diet- fish size- grow-out- golden rabbitfish

Topic: Sustainable Aquaculture and Fisheries