Potential use of the sea lettuce Ulva lactuca replacing soybean meal in the diet of the black tiger shrimp Penaeus monodon juvenile

Abstract

To evaluate the biological value of incorporating the sea lettuce Ulva lactuca meal in the diet of the black tiger shrimp (Penaeus monodon), 3 diets were fed to groups of shrimps containing two levels (15% and 30% replacement of soybean meal) of the sea lettuce for 90 days. Biological parameters were determined either periodically or at the termination of the experiment. Specific growth rate (SGR) of shrimp fed the control diet and those fed with the diet containing 15% replacement were not significantly different from each other while that of shrimp fed 30% soybean replacement was slightly but significantly inferior. All other parameters such as survival rate, feed intake, food conversion efficiency, protein efficiency ratio protein and lipid deposited and body composition were all statistically similar between the experimental groups of shrimp. Thus, the 30% replacement level or 10.5% inclusion level could be used in the diet of the shrimp P. monodon. When performances were compared with the best result in incorporating U. lactuca protein concentrate from a previous study and that in the present study (both were 30% replacement or 10.5 inclusion level), they were statistically similar. Thus, the raw U. lactuca meal is recommended because it did not require additional processing to produce the concentrated seaweed.