Protein and amino acids are expensive nutrients in feed; an oversupply of crude protein is the main cause of nitrogen contamination of pond water and environmental pollution. Reducing protein content of feed, while satisfying amino acid requirements of shrimp can reduce production costs and nitrogen pollution. Generally, shrimp diets are formulated in terms of crude protein (CP) and amino acids content without considering the bioavailability of these ingredients.
The quality of protein sources is expressed as the amount of essential amino acids in the CP. This information is important, but is not sufficient for optimizing formulations because digestive utilization of amino acids is always lower
than the analyzed amount. Data on amino acid digestive utilization coefficients is one of the most important factors in preparing adequate shrimp feeds and there is an increasing interest in defining feedstuff quality using as criterion the coefficients of amino acid digestibility. Methionine is the first limiting amino acid in most shrimp diets
; thus, knowledge of its availability, aswell as the contents of other essential amino acids in feedstuffs is an important
basis for determining nutritional quality. Digestibility studies of amino acids are particularly important for feed that includes marine animal ingredients because bioavailability of nutrients is affected by the temperature used during processing and manufacturing of ingredients. There is information on the digestibility of proteins and amino acids from
practical feedstuffs for Pacific whiteleg shrimp; hence, creating a database of digestibility of amino acids could provide more useful, accurate, and flexible information for low cost formulation processes.
However, different factors affect utilization of feedstuffs, such as the raw material, recipient species, whole fish or scraps, freshness, processing methods, and storage conditions of the meal. The purpose of this study was to determine in vivo apparent digestibility of dry matter, protein, and essential amino acid in marine animal feedstuffs used in diets for
whiteleg shrimp Litopenaeus vannamei.