Taurine supplementation increases the potential of fishmeal replacement by soybean meal in diets for largemouth bass Micropterus salmoides

Abstract

The effects of replacing dietary fishmeal by soybean meal with taurine supplementation on feed intake, growth, feed utilization, body composition and waste output of largemouth bass were examined. A control diet (C) contained 400 g/kg fishmeal, 20%, 40% and 60% of fishmeal in diet C was replaced by soybean meal, with or without 5 g/kg taurine supplementation (abbreviated as S20 + T, S40 + T, S60 + T, S20, S40 and S60, respectively). Significantly lower weight gain was found in fish fed diet S60 compared with fish fed diet C (p < 0.05), while no significant difference was found in weight gain between fish fed diet C and fish fed diets S20, S20 + T, S40 + T and S60 + T (p > 0.05). No statistically differences were found in feed intake and feed conversion ratio between fish fed diet C and fish fed diets S20, S20 + T, S40, S40 + T and S60 + T (p > 0.05). No significant differences were found in nitrogen retention efficiency, body crude protein content and nitrogen waste among fish fed different test diets (p > 0.05). This study suggests that dietary fishmeal level for largemouth bass can be reduced to 240 g/kg and further reduced to 160 g/kg with taurine addition, with soybean meal used as a fishmeal substitute.