Effects of source and level of dietary neutral detergent fiber on feed intake, ruminal fermentation, ruminal digestion in situ, and total tract digestion in beef cattle fed pelleted concentrates with or without supplemental roughage.

摘要: The effects of source and level dietary NDF on intake, ruminal digestion in situ, fermentation, total tract were evaluated Hereford steers using a replicated 5 x Latin square design. Diets contained 62 to 64% TDN included 1) 80% control concentrate (contained pelleted ground grains) 20% timothy hay (traditional diet), 2) alfalfa cubes, 3) 90% 10% 4) completely diet corn cobs as the primary source, 5) textured (rolled instead hay. Dry matter intake differed (P less than .05) between traditional cube diets due limited acceptance cubes. Increased osmolality, VFA, NH3 N lower .01) pH fed cob relative preferential consumption over supplemental roughage resultant rapid fermentation concentrates. Potentially degradable DM exceeded .06) all other diets, resulting increased .10) extent disappearance despite slower rate disappearance. Rate situ starch parameters similar traditional, cob, diets. All involving whereas Although formulation with different sources did not affect nutrients, nutrient availability altered differences selection feedstuffs by steers.