Abstract:This research of the backcross progeny of female diploid F1 hybrid(blunt snout bream×topmouth culter)×male blunt snout bream(BTB for short)and its parents topmouth culter(TC),blunt snout bream(BSB)and BT(BSB×TC)investigated the chemical composition of muscle nutrients including moisture,fat,protein and ash,as well as the composition of fatty acid and amino acid.The observations suggested that,compared to the original parents,BTB displayed high protein content and low carbohydrate level.Further analysis of fatty acid revealed that the UFA(unsaturated fatty acids)content in BTB,especially oleic acid,DHA,etc.(P<0.05),was significantly higher than that in other kinds of fish.In terms of amino acids,BTB had higher flavor amino acid ratio than its parents.Taken together,the results provided biochemistry evidences for proving the advantages of BTB in nutritional value and taste.