Supplementation with different protein profiles for grazing beef cattle supplemented in tropical grass during the rainy-dry transition season

The objective of this study was to evaluate increasing levels of inclusion of dry distillery grains (DDGs) in substitution of corn and urea in multiple supplements for beef cattle of Urochloa brizantha cv. Marandu on the consumption, digestibility, and efficiency of microbial synthesis and use of nitrogen. We used four Nellore bulls cannulated in the rumen with an average age of 24 months and 445.12 ± 34.4 kg of body weight (BW), in a 4 × 4 Latin square design. Supplements differed by the inclusion level of DDG (0%, 31.5%, 63.0%, and 94.5%). Increasing levels of DDG inclusion decreased dry matter intake (DMI) ( P = 0.002), forage ( P = 0.002), organic matter (OM) ( P = 0.001), crude protein (CP) ( P = 0.037), and total digestible nutrients (TDN) ( P