Dhanapong
Sangsue, Evonik Degussa (SEA) Pte. Ltd. Technical Sales Manager
Animal protein sources, such as fishmeal, have typically been used in aquatic animal feed to provide essential amino acids and other nutrients, but the nutritional value of these protein sources can vary greatly due to type of species used and processing conditions. Considering the importance of fishmeal in aquatic feeds, it is important to understand this nutrient variation and its impact on production performance if not accounted for. In 2010, 266, 387, 241, 209, and 39 samples of locally-produced fishmeal from Vietnam, Thailand, Philippines, Indonesia, and Malaysia, respectively, were analyzed for the crude protein and amino acid contents. The analyzed crude protein contents of those fishmeal samples ranged from 56.23 to 63.18 %, while methionine contents ranged from 1.34 to 1.75%, and lysine contents ranged from 3.61 to 4.71%. Fishmeal from Indonesia had the highest levels of CP, Met and Lys with 63.18, 1.75, and 4.18%, respectively, whereas fishmeal from Vietnam had the lowest with 56.23, 1.34, and 3.61%, respectively. Fishmeal produced in Thailand had the greatest variation with a coefficient of variation of 9.23% for CP, while Philippines had the most-consistent production with a coefficient of variation of 4.59%. A portion of the variation can be explained by origin of fishmeal and processing. For example, analyses of 87 Tra catfish fishmeal samples from Vietnam (by-products from Pangasius processing) revealed 58.5%, 4.04%, 1.48% of average CP, Met and Lys respectively with coefficients of variation of 6.0%, 12.3%, and 14.2%, respectively. To formulate diets as precisely as possible, it is critical to both understand the amino acid requirements of the aqua species being fed and to understand the nutrient variation in the ingredients that will be used to produce that diet. Without this knowledge, safety margins must be increased, which increase diet cost due to less efficient use of this costly raw material. These data highlight the importance of analyzing fishmeal on a routine basis in order to better understand its nutrient content and the variation contained therein.