9 - Diet Formulation and Manufacture

Abstract

Diet formulation and manufacture are exercises in compromise between the ideal and the practical. The perfect feed formulation that meets the nutritional needs of an animal or fish must always be modified to be less than ideal so that it can be manufactured. Diet formulation and manufacture are not independent activities. When feeds are formulated, the pelleting characteristics of mixtures are just as important as the nutritional content of the mixture. Production diets must be economical to manufacture, ship, store, and deliver to the fish. Pellets must remain intact in water until fish consume them. This ensures adequate intake of nutrients that might otherwise leach out of the pellets and minimize water pollution caused by disintegrating pellets. Thus, the way in which feed ingredients are chosen, prepared, combined, and processed is influenced by many factors, and compromise between the ideal and the practical is a necessity requiring a solid foundation of knowledge and experience. Rising concerns about the effects of fish farming on the aquatic environment, coupled with concerns about the dependence of fish feeds on fish meal produced from fully utilized or over-utilized wild fish stocks, have also influenced fish feed formulation and manufacture.