DDGS can offer low-fat optionURBANA, Ill. — Dried distillers grains with solubles (DDGS) are a coproduct of the ethanol industry and have been an affordable source of energy and protein in swine diets for decades.
By: University of Illinois, Urbana,
URBANA, Ill. — Dried distillers grains with solubles (DDGS) are a coproduct of the ethanol industry and have been an affordable source of energy and protein in swine diets for decades.
In recent years, ethanol plants have begun to centrifuge the solubles from ethanol production to extract oil, which is sold to the biodiesel industry. Researchers at the University of Illinois are evaluating these low-fat DDGS products for use in swine diets.
“Dietary fat concentration has been shown to be a factor in the digestibility of nutrients,” says Hans Stein, a professor of animal sciences at University of Illinois. “Because DDGS supplies a significant amount of protein in swine diets, we wanted to investigate if amino acid digestibility is compromised in diets containing low-fat DDGS.”
Stein’s team compared amino acid digestibility in growing pigs fed diets containing conventional DDGS or one of two sources of low-fat DDGS. The conventional DDGS contained 11.5 percent fat, whereas the two low-fat DDGS sources contained 7.5 and 6.9 percent fat, respectively.
“We observed that the standardized ileal digestibility of almost all amino acids was greater in conventional DDGS than in either source of low-fat DDGS,” Stein says.
The team also investigated if adding fat to the low-fat DDGS diets improves amino acid digestibility. Corn oil was added to the low-fat DDGS diets with the intent to bring the concentration of fat in these diets to the same level as in the diet containing conventional DDGS.
“Adding dietary fat to diets containing low-fat DDGS didn’t improve the digestibility of amino acids,” Stein explains. “That result was somewhat surprising because it conflicted with previous data.”
But, he notes that in previous experiments, the differences in fat levels between diets without or with added fat were much greater than in the current study.
Stein adds that based on these observations, feed companies and swine producers using low-fat DDGS might have to formulate diets based on reduced values for the standardized ileal digestibility of amino acids compared with values for conventional DDGS.
The study, “Amino acid digestibility in low-fat distillers dried grains with solubles fed to growing pigs,” was published in a recent edition of the Journal of Animal Science and Biotechnology.