This Is AuburnElectronic Theses and Dissertations

Lipid Extracted Distillers Dried Grains with Solubles (LE-DDGS) as a Partial Replacement for Soybean Meal in Hybrid Tilapia (Oreochromis niloticus x Oreochromis aureus)




Chatvijitkul, Sirirat

Type of Degree



Fisheries and Allied Aquacultures


Feed costs are primarily driven by the cost of protein sources used to produce the feed. Substitution of expensive protein sources with lower cost ingredients would potentially reduce the cost of the feed. Lipid-extracted distillers dried grains with solubles (LE-DDGS) is a relatively new product of distillers dried grains (DDG) which could be used as alternative feedstuffs in tilapia feed formulations. Compared to other plant-based protein sources, DDGS has moderate protein and higher fiber contents. Tilapia require a relatively low level of protein and can utilize high inclusion level of plant-based proteins. Given the relatively low price, LE-DDGS may be a suitable alternative protein source in hybrid tilapia diet. Hence, two growth trials were conducted to evaluate the substitution of soybean meal with LE-DDGS in practical diets for the hybrid tilapia (O. niloticus × O. aureus). Results from these studies indicated that formulated diets containing increasing percentages of LE-DDGS without lysine supplementation resulted in a reduced growth of hybrid tilapia. However, positive performances including growth, feed conversion ratio, survival, protein retention, and energy retention were demonstrated in fish fed diet using 40 % LE-DDGS of diet with lysine supplementation. Moreover, the inclusion of LE-DDGS at 50% of diet with lysine and an additional 2% lipid promoted good growth in hybrid tilapia. Overall, results from these studies revealed that LE-DDGS with lysine supplement is a promising protein source in combination with soybean meal in formulated diets containing approximately 36% protein for hybrid tilapia.