Supplemental effects of coated methionine and/or lysine to soy protein isolate diet for juvenile kuruma shrimp, Marsupenaeus japonicus

A 6-week feeding trial was conducted using six test diets to examine the effects of coated or non-coated methionine and/or lysine supplemented to soy protein (SPI)-based diet on the performance of juvenile kuruma shrimp, Marsupenaeus japonicus. Test diets were fed to triplicate groups of shrimp (about 0.4 g) for two times a day. The shrimp fed the diets supplemented with coated methionine or lysine trended to higher weight gain compared to shrimp fed the diet without supplementation of the amino acids. The juveniles fed the diet containing both coated methionine and lysine showed significantly higher growth performance than those fed the diet contained non-coated methionine and lysine. Apparent feed intake and survival were not influenced by the supplementation of methionine and lysine. The whole body proximate, total amino acid and free amino acid composition showed few differences among the groups. This study indicated that the supplementation of coated methionine and lysine was effective in improving the nutritive value of SPI deficient in methionine and lysine for juvenile kuruma shrimp.