The Use of Water Exchange for Feeding Rate and Growth Promotion of Shortfin Eel Anguilla bicolor bicolor In Recirculating Water System

Abstract

Growth and feed rate accompanied with proximate, texture and condition of the organism. The objective of this study was to obtain the effect of different diets to the feed rate and growth of shortfin eel Anguilla bicolor bicolor. The study used three replications and 3 treatments of different sources of feed diet during 84 days culture. The fish were fed with proximation of 2.2% wet basis d-1 (ratio of dry feed and water = 4 : 3). Initial density of approx. 15 kg seed stock of eel fingerling size (early elver) per m3 water in the recirculating water system with ranging of means±SD of temperatures, pH and DO were 27.14±0.11 to 27.66±0.05 °C, 7.44±0.09 to 7.66±0.05, and 3.54±0.19 to 4.66±0.09 ppm respectively. The result shows that feeding rate has relation to lipid content of feed but not significantly different among treatments (α > 0.05), the highest FR shows by F2 followed by F3 and F1=2.04±0.07% d-1 and F2 = 2.12±0.05% d-1 and F3= 2.10±0.06% d-1). Absolute growth of individuals and biomass were related to the protein content; the highest was F1 and F3. Growth margin F1, F2 and F3 of individual were 25 g (46%), 22 g (44%), and 15 g (27%) respectively, whilst biomass margin were 3,855 g (26%), 3,629 g (24%), and 2,834 g (18%) respectively during 70 days culture. Marginal mean of Individual-specific growth rate (SGRi) shows no significantly different (α > 0.05) between F1(0.52±0.01% d(0.35±0.07% d -1-1), but both of F1 and F2 2, where: F1 followed by F2 (0.53±0.05% d-1have significantly different (α < 0.05) to F3). Biomass-specific growth rate (SGRb) also shows no significantly different (α > 0.05) between F1 (0.33±0.09% d-1) and F2 (0.31±0.02% d-1), but both of F1 have significantly different (α < 0.05) to F3 (0.24±0.08% d-1 ).