Effects of feeding distillers dried grains with solubles, high-protein distillers dried grains, and corn germ to growing-finishing pigs on pig performance, carcass quality, and the palatability of pork

An experiment was conducted to investigate pig performance, carcass quality, and palatability of pork from pigs fed distillers dried grains with solubles (DDGS), high-protein distillers dried grains (HPDDG), and corn germ. Eighty-four pigs (initial BW, 22 ± 1.7 kg) were allotted to 7 dietary treatments with 6 replicates per treatment and 2 pigs per pen. Diets were fed for 114 d in a 3-phase program. The control treatment was based on corn and soybean meal. Two treatments were formulated using 10 or 20% DDGS in each phase. Two additional treatments contained HP-DDG in amounts sufficient to substitute for either 50 or 100% of the soybean meal used in the control treatment. An additional 2 treatments contained 5 or 10% corn germ, which was calculated to provide the same amount of fat as 10 or 20% DDGS. Results showed that for the entire experiment, pig performance was not affected by DDGS or HP-DDG, but final BW increased (linear, P < 0.05) as corn germ was included in the diets. Carcass composition and muscle quality were not affected by DDGS, but LM area and LM depth decreased (linear, P < 0.05) as HP-DDG was added to the diets. Lean meat percentage increased and drip loss decreased as corn germ was included in the diets (quadratic, P < 0.05). There was no effect of DDGS on fat quality except that belly firmness decreased (linear, P < 0.05) as dietary DDGS concentration increased. Including HP-DDG or corn germ in the diets did not affect fat quality, except that the iodine value increased (linear, P < 0.05) in pigs fed HP-DDG diets and decreased (linear, P < 0.05) in pigs fed corn germ diets. Cooking loss, shear force, and bacon distortion score were not affected by the inclusion of DDGS, HP-DDG, or corn germ in the diets, and the overall palatability of the bacon and pork chops was not affected by dietary treatment. In conclusion, feeding 20% DDGS or high levels of HP-DDG to growing-finishing pigs did not negatively affect overall pig performance, carcass composition, muscle quality, or palatability but may decrease fat quality. Feeding up to 10% corn germ did not negatively affect pig performance, carcass composition, carcass quality, or pork palatability but increased final BW of the pigs and reduced the iodine value of belly fat.