In a study with gilthead sea bream, two test diets used primarily soy products as sources of protein and fat against a reference feed based largely on fishmeal and fish oil.
The National Oceanic and Atmospheric Administration and U.S. Department of Agriculture joined forces through the NOAA-USDA Alternative Feeds Initiative to identify feed ingredients that will reduce the amount of fishmeal and fish oil in aquaculture feeds while maintaining the human health benefits of seafood. Through research on a variety of sources, promising alternatives are beginning to emerge.
The authors performed nutrition studies to determine a maximized efficiency of yield in spotted sea trout. Fry were “forced” to swim against a steady current to gauge the effectiveness of increased exercise.
In a white shrimp farm trial in a low-salinity environment, alternatives to fishmeal did not negatively impact the growth, survival or FCR of the shrimp.
Most marine fish have pelagic eggs with large pools of free amino acids of fairly constant proportion regardless of species. The amino acids provide energy for metabolism and are an important nutritional asset for growing embryos.
Recent research by the authors evaluated strategies to reduce fishmeal and fish oil in diets for red drum by substituting terrestrial proteins and lipids while maintaining beneficial fatty acids with DHA supplements derived from marine algae.
Shrimp farm trials demonstrated the feasibility of fishmeal replacement with soybean and corn gluten meal with little adverse effect on production performance.
Results of studies indicate that soy protein concentrate can be substituted for fishmeal in diets for common carp, grass carp, tilapia and channel catfish fingerlings raised in ponds and cages.
In a study, krill meal incorporated into shrimp diets replaced fishmeal and soy lecithin with no significant effect on shrimp performance.
A laboratory study indicated gilthead sea bream can be grown on feeds in which fishmeal and fish oil levels are reduced from traditional values using soy products.
Production goals may call for specialized diets to meet market or other demands. An evaluation of feed management strategies can optimize culture conditions and maintain efficiency.
Although their aquafeed manufacturing process features are similar, twin-screw extruders offer more operational flexibility than single-screw extruders.
Based on thorough knowledge of the culture species, feed formulations must deliver protein and energy, and a balance of nutrients in a palatable form consumed with little waste.
In a study, ground barley containing different levels of beta-glucan was substituted for wheat in experimental diets fed to rainbow trout.
The large-scale shift of corn from animal feed to ethanol production is a potentially disruptive force in the feed ingredient world.
In a meta-analysis of 28 nutrition studies, the authors found limited possibilities for ingredient substitution for fishmeal in diets for salmon and trout.