Effects of Size Variation and Stocking Density on the Growth and body composition of the Mandarin Fish, Siniperca scherzeri

Abstract

This study investigated the effect of size variation and stocking density on the growth and body composition of mandarin fish, Siniperca scherzeri, in two size groups: small size group(50.2g/fish) and large size group (173.1g/fish). Small size group and large size group were fed one of the experimental diets twice daily for 10 weeks and 15 weeks respectively. At the end of the feeding trial in small size group, weight gain and specific growth rate of fish density 4kg/m3 were lower than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3 . Daily feedintake and daily protein intake of fish density 4kg/m3 were lower than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3. Protein efficiency ratio of fish density 4kg/m3 were higher than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3. At the end of the feeding trial in large size group, weight gain of fish density 6kg/m3 were higher than those of fish density 4.5kg/m3, fish density 3/m3 and fish density 1.5kg/m3 in 5 weeks, weight gain of fish density 4.5kg/m3 and 6kg/m3 were higher than those of fish density 3kg/m3 and fish density 1.5/m3 in 10 weeks. Based on these results, the optimum stocking density for mandarin fish size(50g) is 3kg/m3, the optimum stocking density for mandarin fish size(173g) is 4.5kg/m3.ize group and large size group were fed one of the experimental diets twice daily for 10 weeks and 15 weeks respectively. At the end of the feeding trial in small size group, weight gain and specific growth rate of fish density 4kg/m3 were lower than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3 . Daily feedintake and daily protein intake of fish density 4kg/m3 were lower than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3. Protein efficiency ratio of fish density 4kg/m3 were higher than those of fish density 3kg/m3, fish density 2kg/m3 and fish density 1kg/m3. At the end of the feeding trial in large size group, weight gain of fish density 6kg/m3 were higher than those of fish density 4.5kg/m3, fish density 3/m3 and fish density 1.5kg/m3 in 5 weeks, weight gain of fish density 4.5kg/m3 and 6kg/m3 were higher than those of fish density 3kg/m3 and fish density 1.5/m3 in 10 weeks. Based on these results, the optimum stocking density for mandarin fish size(50g) is 3kg/m3, the optimum stocking density for mandarin fish size(173g) is 4.5kg/m3.