The effect of additional arginine in the high defatted soybean meal diet on the growth of giant gouramy Osphronemus gouramy Lac

Four experimental diets were used to determine the effect of additional arginine in the high defatted soybean meal (DSM) diet on the protein retention and the growth of giant gouramy, Osphronemus gouramy Lac. Diet A contained 50% of the protein from brown fish meal (BFM) and 50% from DSM; diet B contained 50% BFM and 50% DSM plus 0.70% arginine; diet C contained 25% BFM and 75% DSM and diet D contained 25% BFM and 75% DSM plus 0.60% arginine. Fish, with mean bodyweight of 21.6 ± 1.13 g, were fed on the experimental diets for 56 days. The DSM diet (diet C) produced lower protein retention (PR), lipid retention (LR), feed efficiency (FE) and daily growth rate (DGR) than diet A (50% BFM + 50% DSM). The addition of arginine in diet D (75% DSM in dietary protein) can improve the DSM quality, which was shown by producing the same PR, LR, FE, and DGR as in diet A. These results indicated that arginine is one of the important essential amino acids for the high defatted soybean meal diet of giant gouramy.