Feeds for farming marine shrimp: performance and feed protein digestibility as criteria for diet development and quality control

Abstract

Aquaculture has become na important provider of animal protein for humanity. The increasing supply of farmed shrimp and fish has to necessarily associated with rising aqua feed consumption. Feed manufacturing and management is crucial for either technical and economical development but also regarding environmental sustainability of farming practices. With stable food supplies by capture fisheries the competition for conventional feed ingredients as fish meal and oil is increasing that impose the use of alternative proper quality dietary sources. On the other hand, feed is a potential contributor for water eutrophication due to inadequate feeding management and use of poor digestibility feeds. Methods for determination of digestibility in the live animal may be practical tools for quality assessment of ingredients and finished feeds. The present project aims to advance in the assessment of feed quality for farmed shrimp in terms of performance and protein digestibility. Thus, methods for digestibility determination will be evaluated, and commercial and experimental diets will be assessed for juvenile L. vannamei: (1) Different commercial diets available for farmed shrimp will be sampled and analyzed for proximate composition, species-specific and in vitro protein digestion, (2) The classical method for evaluation of ingredient digestibility (replacement upon a reference diet) will be applied using three different ingredients at three inclusion levels. (3) The utility of a dietary fraction (acid insoluble ash) as internal marker will be tested for determination of apparent nutrient digestibility. (4) The combined effect of different diet formulations and nutritional regimes upon shrimp performance and digestibility will determined with three diets applied ate 0.75, 1.5 and 3% of shrimp biomass per day. (AU)