Effects of Low-Protein Dried Distillers' Grains With Solubles in High-Concentrate Diets for Finishing Lambs

This study evaluated the effects of increasing inclusion levels of low-protein dried distillers' grains with solubles (DDGS) in high-concentrate diets on nutrient intake, digestibility, nitrogen balance, and ingestive behavior of finishing lambs. Four Santa Inês crossbred, uncastrated male lambs (24.8 ± 1.0 kg body weight) were assigned to four dietary treatments in a 4 × 4 Latin square design. Treatments consisted of a control diet without DDGS and diets containing 200, 400, or 600 g/kg dry matter (DM) of low-protein DDGS. DM and TDN intakes showed quadratic responses (p < 0.05) to DDGS inclusion. Neutral detergent fiber intake increased linearly, whereas NFC intake decreased linearly (p < 0.05). Inclusion of DDGS did not affect (p > 0.05) apparent digestibility of DM, CP, or EE. However, NDF digestibility increased linearly by 4.99 g/kg per unit of DDGS added. Nitrogen retention, plasma urea nitrogen, and blood glucose were not affected. Rumination time increased linearly (p < 0.05). Low-protein DDGS can be included at 600 g/kg DM in finishing lamb diets. However, including 200 or 400 g/kg DM may result in negative associative effects for some variables. Overall, low-protein DDGS remains a valuable feed ingredient for substituting ground corn and soybean meal.