Nutritional requirements, feed formulation, and feeding practices for intensive culture of the freshwater prawnMacrobrachium rosenbergii

Research results concerning nutrition of the freshwater prawn Macrobrachium rosenbergii and applicability to the production of feed for intensive culture are presented. Future research approaches are recommended and comparisons to the nutrition of penaeid shrimp species are provided. Quantitative requirements of essential amino acids for M. rosenbergii are undefined; however, arginine, methionine, and lysine are suspected as being the first limiting amino acids in commercially formulated feeds. The proportion of each essential amino acid in the tissue of shrimp provides a good guideline for the determination of dietary requirements. Optimal dietary protein: energy ratios in shrimp feeds appear to be dependent on the ability to digest carbohydrates. The digestibility of potential protein sources in commercial feeds needs to be evaluated through in vitro studies using natural enzyme extracts. Levels of lipids in freshwater prawn diets can be as low as 2% if sufficient dietary energy is available and the requirement for polyunsaturated fatty acids is satisfied. Juvenile M. rosenbergii require >20 carbon unit polyunsaturated fatty acids at a dietary level of approximately 0.1%, lower than the reported requirements of penaeid shrimp. Representatives from the linolenic and linoleic families appear to be equally effective in satisfying the requirement. Dietary phospholipids confer a growth‐enhancing effect on penaeid shrimp, but the effect of dietary phospholipids for M. rosenbergii remains undefined. M. rosenbergii and all other shrimp species studied to date require dietary cholesterol, but the possible benefit or sparing effect of phytosterols remains to be sufficiently investigated. Information concerning requirements of water‐soluble vitamins and minerals is lacking due to the combined effects of leaching and feeding behavior, which influence amounts actually consumed. M. rosenbergii has a vitamin C requirement similar to that reported for fish. Feeding strategies need to be based on efficient delivery of nutrients and the stage of growth. Processing suitability, availability, and chemical composition place restrictions on the number of feedstuffs that can be successfully incorporated into a feed. In ponds, an effective feeding strategy may reside in a procession from exclusive provision of organic material that stimulates the detrital food chain to feeding a water‐stable, nutritionally well‐balanced, formulated feed. Contribution of natural pond productivity to satisfaction of nutritional requirements decreases as the resident shrimp biomass in a pond increases. Feeding rates per unit body weight can be minimized through the use of a water‐stable feed and feed ingredients that are highly digestible.