BOARD-INVITED REVIEW: The use and application of distillers dried grains with solubles in swine diets

Distillers dried grains with solubles (DDGS) may be included in diets fed to pigs in all phases of production. The concentrations of DE and ME in DDGS are similar to those in corn. Phosphorus in DDGS is highly digestible to pigs and apparent total tract digestibility values of approximately 60% have been reported. The concentration of starch in DDGS is low (i.e., between 3 and 11%), but the concentration of fat in DDGS is approximately 10% and the concentrations of ADF, NDF, and total dietary fiber in DDGS are approximately 3 times greater than those in corn (9.9, 25.3, and 42.1%, respectively). The apparent total tract digestibility of dietary fiber is less than 50%, which results in reduced digestibility values for DM and energy in DDGS. The concentrations of most AA in DDGS are approximately 3 times greater than those in corn, but the standardized ileal digestibility of most AA is approximately 10 percentage units less than in corn. Nursery pigs from 2 to 3 wk postweaning, and growing and finishing pigs may be fed diets containing up to 30% DDGS without any negative impact on growth performance. However, the carcass fat in pigs fed diets containing DDGS has a greater iodine value than the carcass fat in pigs not fed DDGS. It may, therefore, be necessary to withdraw DDGS from the diet of finishing pigs during the final 3 to 4 wk before slaughter to achieve the desired pork fat quality. Lactating sows can also be fed diets containing up to 30% DDGS, and DDGS can replace all the soybean meal in diets fed to gestating sows without negatively affecting sow or litter performance. Inclusion of DDGS in diets fed to pigs may improve immune system activation, but more research is needed to elucidate the mechanisms responsible for these effects. Manure volume will increase when DDGS is included in the diets because of the reduced digestibility of DM in DDGS. Nitrogen excretion may also increase, but this can be prevented by the use of crystalline AA in diets containing DDGS. In contrast, P excretion can be reduced in diets containing DDGS if the total dietary concentration of P is reduced to compensate for the greater digestibility of P in DDGS. In conclusion, DDGS can be included in diets fed to growing pigs in all phases of production, beginning at 2 to 3 wk postweaning, in concentrations of up to 30% DDGS, and lactating and gestating sows can be fed diets containing up to 30 and 50%, respectively, without negatively affecting pig performance.