DIGESTIBILITY AND UTILIZATION OF PEARL-MILLET DIETS FED TO FINISHING BEEF-CATTLE

Pearl miller grain waS blended with corn in 1:1 or 2:1 ratios in beef finishing diets fed in two metabolism and two feedlot trials. in Exp. 1, diets contained 1) 79.5% corn and 4.5% soybean meal (C-SBM), 2) 28% corn, 54.5% sorghum, and 1.5% soybean meal [GSC(2:1)], and 3) 28% cor n and 56% pearl millet [PMC(2:1)]. In Exp. 2, diets contained 1) 81.5% corn and 3.5% soybean meal (C-SBM) or 2) 42.5% corn and 42.5% pearl m illet [PMC(1:1)]. Diets fed to steers in metabolism trials in Exp. 1 a nd 2 had similar (P >.10) apparent digestion coefficients for OM, crud e fiber, NDF, and ADF. However, ether extract digestibility was higher (P <.05) for C-SBM than for GSC(2:1) and PMC(2:1) in Exp. 1, and it w as higher(P <.10) for C-SBM than for PMC(1:1) in Exp. 2, Tn both exper iments CP digestibility was higher (P <.10) for C-SBM diets, and N ret ention was similar (P >.10) for diets within each experiment. In each experiment, TDN calculated from apparent digestion coefficients was co nverted to NE, and NE(g). The TDN, NE(m), and NE(g) were lower (P <.10 ) for g GSC(2:1) and PMC(2:1) than for C-SBM in Exp. 1. Experimental d iets were fed to steers (n = 45; 396 +/- 19 kg initial BW; 70-d ad lib itum feeding) in Exp. 1 and to heifers (n = 30; 318 +/- 15 kg initial BW; 92-d ad libitum feeding) in Exp. 2. The ADG, empty body weight gai n (EBG), and predicted EBG were not different (P >.10) for diets compo sed of the different grain sources. Feed DMI and DM per gain were high er (P <.05) for PMC(1:1) than for C-SBM in Exp. 2. Pearl millet suppli ed approximately 88% as much NE(m) and 85% as much NE(g) as the corn-S BM portion of diets having similar CP concentrations.