水産養殖研究開発ジャーナル

概要

Energy Partitioning by Litopenaeus Vannamei (Boone, 1931) given Plant Protein Diets

Suárez JA *,Gaxiola G ,Posso R ,Garcia G ,Alanis G ,Suárez A ,Faillace J ,Cuzon G

The nutritive value of soybean meal (SBMd), feed pea meal (FPMd) and canola meal (CNAd) was evaluated for the shrimp L. vannamei. The apparent digestive coefficient (ADC) of dry matter (DM) varied from 80-86% for diets (p<0.05) and 64-87% for ingredients (p<0.05). ADC protein varied in a narrow range but still differed amongst diets (p<0.05); CNA provided the least ADC protein. ADC energy followed the same pattern as ADC protein but the range of variation was higher (87-92%) than with protein. All parameters derived from oxygen consumption were measured to determine an energy budget calculated on a 24 h basis, with animals weighing 6 g on average and given practical diets. SBMd and FPMd yielded recovered energy (RE) of 0.9 and 0.7kJ, respectively, in comparison to CNAd, which yielded a value as low as 0.4 kJ RE. The latter thus represents a poor diet alternative as compared to soy or pea meal diets in terms of energy use for growth. Substrates were provided to shrimp at a high level and trypsin was able to hydrolyze all protein sources similarly. The result of this process was protein with tertiary structures. Such structures could be attacked in peptide chain regions where radical –COOH is present and at Arg and Lys linkages. A priori, the results of hydrolysis would release the same amount of amino acid. Therefore, any difference in ADC will be derived from the presence of inhibitor or from excess nitrogen-free extract. This could explain the lower ADC protein value observed with CNA. Diets fed to shrimp led to an energy budget where a large part of the energy was derived from catabolism of amino acids. Such budgets typically reflect a better output from SBM and FPM as compared to CAN. Therefore, we conclude that ADC is a useful tool for evaluating vegetable-derived protein in the formulation of shrimp diets.