Addition of Supercritical CO2 Extracted Mussel Meal in Fishmeal-Free Diets Improved Growth of Penaeus monodon juveniles

Abstract

Supercritical CO₂ extracted mussel meal (SCMM) is a by-product of green lipped mussel (Perna canaliculus) processing, following the removal of shell and therapeutically active lipids. The efficacy of SCMM as an ingredient in diets for Penaeus monodon was evaluated in two formulations using fishmeal (FM) and zero-FM (ZFM) diets at 10% inclusion. Growth, nutrient retention and apparent digestibility (AD) were measured. The anti-inflammatory properties of SCMM, among several other ingredients, were also analysed using an in vitro assay. Although the commercial diet was a superior-performing diet, SCMM addition benefited the ZFM formulations whereby the ZFM + 10% SCMM diet matched the performance of the commercial diet for final weight (4.51 vs. 4.78 g/shrimp), weight gain (WG) (3.72 vs. 4.02 g/shrimp), tank biomass (31.38 vs. 35.25 g/shrimp) and feed conversion ratio (FCR) (1.7 vs. 1.2), respectively. SCMM addition had no effect on growth performance of the FM diet and did not affect nutrient retention of the FM or ZFM diets. AD of protein and the sum of amino acids of SCMM was found to be high at 70%, for both. Specifically, digestibility of methionine, lysine and arginine were 61%, 78% and 84%, respectively. SCMM exhibited an anti-inflammatory capacity that was lower than a positive control, quercetin, but higher compared to several ingredients including FM. SCMM’s inherent bioactive compounds, including omega-3 fatty acids, glycosaminoglycans (GAGs), betaine and potential anti-inflammatory agents, are suggested as contributors to the improved growth performance. The results indicate that SCMM could be strategically used to produce innovative high performance diets free of FM for P. monodon, using a low 10% inclusion level. In addition, as a by-product of another industry, use of SCMM promotes waste valorisation and resource circularity.