Nutritional evaluation of distiller's dried grain with soluble (DDGS) as replacement to soybean meal in diets of milkfish, Chanos chanos and its effect on fish performance and intestinal morphology.

Roger Edward P. Mamauag^a, Trisha J. Nacionales^a and Janice A. Ragaza^b

^aSoutheast Asian Fisheries Development Center, Aquaculture Department, Tigbauan, Iloilo, Philippines, 5021.

^bDepartment of Biology, Ateneo de Manila University, Katipunan Ave., Loyola Hts., Quezon City, NCR, Philippines, 1108.

A 90-day feeding trial was conducted on milkfish, Chanos chanos with an initial mean body weight of 3.07±0.17g. Six treatment diets were formulated to contain 0 (Diet 1), 15 (Diet 2), 25 (Diet 3), 30 (Diet 4), 35 (Diet 5) and 45% (Diet 6) DDGS. All the dietary treatments were isonitrogenous (38% crude protein) and isolipidic (6% crude fat). Result of the feeding trial indicated that growth rates, feed intake and feed efficiency was not significantly (P>0.05) affected by inclusion levels of DDGS by up to 45% in the feed. Proximate body composition (crude protein, crude fat, ash, fiber) in fish fed the dietary treatments were not significantly (P>0.05) affected as well. The DDGS when used as a milkfish ingredient has a protein digestibility of 91%, fat digestibility of 85%, carbohydrate digestibility of 75% and a dry matter digestibility of 52%. Results from the intestinal morphology displayed no apparent pathological changes in the digestive tract of fish fed all dietary treatments. These results indicate that DDGS can be efficiently utilized by milkfish by up to 45% without negatively affecting performance parameters and intestinal morphology.