October 30, 2007

US research shows DDGS a better aquafeed than soy-corn

DDGS may be able to provide protein for fish at a lower cost than the soy-corn combinations commonly used, according to research by Agricultural Research Service (ARS).

DDGS is relatively protein-rich and lacks some of the undesirable characteristics that make many plant protein sources less suitable for use in fish feeds, the research showed. Moreover, it is cheaper and more palatable to fish compared to soy-corn combinations.

One drawback, however, is that it is lacking in some essential amino acids, such as lysine.

The results were derived from the ARS Aquatic Animal Health Research Unit at Auburn, Alabama, where nutrition scientist Chhorn Lim and his colleagues are studying how DDGS influence growth performance and disease resistance in catfish and tilapia.

Fish were fed DDGS at inclusion levels of 0, 10, 20, 30 or 40 percent DDGS. All five feeds had similar levels of energy, protein and fat. His results showed that tilapia thrive on feed with up to 20 percent DDGS. If supplemental lysine were added to the feed, DDGS could be fed to the 40 percent levels.

Catfish thrived on feed at 40 percent levels, supplemented with lysine, the research showed.

Catfish on DDGS diets also had greater resistance to at least one major disease: enteric septicemia of catfish and would be able to resist infection better.

Catfish which were fed on the 20 percent DDGS diet also had significantly higher levels of antibodies than those that were not fed on DDGS.