Impact of Urea on Corn Silage Growing Cattle Diets

© The Board Regents of the University of Nebraska. All rights reserved. used for diet adaptation and d 17 to 21 used for sample collection. Titanium dioxide (5 g) was dosed through the rumen cannula at 0800 and 1700 h daily to determine fecal output in periods 1 and 2 (10 g per day). During periods 3 and 4, 8 g TiO2 was used to move the average sample concentration of marker closer to the center of the standard curve of known standards (16 g per day). On d 17 to 20, fecal grab samples (0.55 lb) and duodenal flow contents (250 mL) were collected four times daily at 0800, 1200, 1400, 1800 h. Whole rumen contents (4.5 lb) were collected at 1600 h (8 h postfeeding) on d 20 of each period to isolate bacterial pellets. Duodenal and bacterial composites were analyzed for purine concentration to determine duodenal flow of MCP.