| Four types of poly unsaturated fatty acids (PUFA) are essential for all shrimp species, linoleic (LOA, 18:2n-6), alfa-linolenic (ALA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic (DHA, 22:6n-3) acids. Moreover, the arachidonic acid (ARA, 20:4n-6), even when present, seems to be, in crustaceans, not so important or yet dispensable. It is relevant knowing that cholesterol as much as PUFA are not well absorbed when not followed by a substantial amount of lecithin, reaching 5% of the ration. The sum of PUFA reaches around 3% of the diet, even varying according to the species, stage and ration type. For Penaeus monodon a complex mathematic model was formulated in order to describe the relationships between the requirements of the cited PUFA.... |
