Evaluation of soybean meal from selected cultivars of soybeans for use in practical diets for L. vannamei

Abstract

This study was designed to evaluate the efficacy of twelve sources of soybean meal (SBM), which included new soy varieties in practical feed formulation for Pacific white shrimp, Litopenaeus vannamei, using both digestibility and growth trials. Apparent digestibility coefficients for dry matter (ADMD), energy (ADE) and protein (ADP) were determined in L.vannamei using chromic oxide as inert marker and the 70:30 replacement technique. Digestibility coefficients for ADMD, ADE and ADP ranged from 71.3% to 88.3%, 76.6% to 91.3% and 93.6% to 99.8%, respectively. In general, two distinct groups of high and moderate digestibility values were observed. Selected soybean meals were run in an 8-week growth trial with six replicate tanks per dietary treatment (10 shrimp per tank, initial weight 0.52 ± 0.04 g). A soybean meal-based reference diet was formulated using commercial soybean meal (52.7% diet), which was then completely replaced on iso-nitrogenous basis with other experimental soybean meals. Significant differences (P > 0.05) were observed in growth but not survival. The shrimps’ final mean weights (5.73-7.60g), weight gains (4.90-6.81g), percent weight gains (508-864%), survivals (75.0-92.0%), and FCRs (1.7-2.4) were within typical limits. In general, the results and trend of digestibility data was similar to that of the growth trial with ingredients I-16, I-17, I-18, and I-19 demonstrating relatively higher values in digestibility and growth. These varieties have a potential to increase the nutritional values of soybean meal for shrimp feeds.