REDUCED DEPENDENCE ON FISH MEAL IN SHRIMP FEEDS WITH USE OF FEED CONCENTRATE

S. Blezinger1, F. Olbrich1, K. Karges1, B. Hill1, A. Bharadwaj2 and G. Chamberlain2
1 H. J. Baker & Bro., Inc., Westport, CT 06880 USA sblezinger@bakerbro.com
2 Integrated Aquaculture International (iAqua), St. Louis, MO 63129 USA anantb@iaqua.com

Global supplies of fish meal have remained static at 6 million metric tonnes per year but demand continues to grow due to growth of the aquaculture industry worldwide. Aquaculture grew by 97% in the decade between 2000 -2010 and its consumption of global fish meal supplies increased from 33% - 73%.  Aquaculture feeds have outcompeted other livestock feeds for the limited supplies of fishmeal.  Fish meal prices have tripled since 2004 due to economic, climatic and other factors.  The predicted growth of the aquaculture industry will exceed global supplies of fish meal thereby necessitating the use of alternate protein sources. Alternate sources include  oilseeds (soybean meal, canola meal, corn gluten meal), protein concentrates (soy protein concentrate, corn protein concentrate), rendered animal proteins (feather meal, poultry meal, meat and bone meal and blood meal), microbial meals, algal meals and some relatively new products such as insect and worm meals.

Fish meal is a complex mixture of nutrients and organic compounds and replacing it in aquatic animal feed formulations involves more than replacing protein.  It is a source of essential and non-essential amino acids, highly unsaturated fatty acids, phospholipids, cholesterol, vitamins and minerals, nucleotides, attractants, bioactive compounds and growth promoters.  Numerous alternate protein sources have been used to replace or reduce fish meal in aquatic feeds but each of these vary in their nutrient composition and nutrient availability. Alternate protein sources may be limiting in one or more nutrients and often a combination of several ingredients may be required to meet the nutrient requirements of an animal.  Such replacement strategies may result in the over fortification of feeds and it is a common practice to supplement with crystalline amino acids to meet the requirements of a variety of targeted species.  A proper balance of amino acids is required achieve optimal protein synthesis and animal performance can be limited by amino acid deficiencies.  Hence, supplementation is used to meet the requirements of the animal and will vary by species.

Shrimp are slow feeders and locate feed by smell which requires extended periods of time.  They also break down pellets into smaller particles prior to ingestion. This leads to significant losses of conventional dietary or supplemented amino acids and other nutrients due to leaching before the shrimp consumes the feed.  H. J. Baker and iAqua have developed a feed concentrate that closely resembles fish meal in its nutrient composition. This feed concentrate consists of several rendered animal proteins and also contains a proprietary amino acid premix that is protected by a heat stable lipid coating.  Leaching tests have shown that losses of amino acids from submerged feeds are reduced by 40% (from 70% to 30%) with the use of protected amino acids.  Feeding trials with the feed concentrate and premix have demonstrated improvements in performance in different species of shrimp. Shrimp fed reduced fish meal or fish meal-free diets containing feed concentrates and the premix exhibited growth rates, feed efficiency and survivability similar to those fed diets containing fish meal.  These results will be presented.