High Dry Matter Zinc Bacitracin-Treated Legume-Grass Silage vs. Untreated High Dry Matter Silage: Each with Corn, Soybran Flakes, and Dried Beet Pulp

Abstract

Summary Zinc bacitracin–treated alfalfa-brome high dry matter silage and similar untreated silage were each fed free-choice with one-third of a pound of hay per 100 lb of body weight per day to similar groups of milking cows. Each silage was fed in a 6 × 6 Latin-square design experiment with three different supplemental grain mixtures containing 15% total protein, in which either ground shelled corn, soybran flakes, or dried beet pulp predominated. The amount of grain fed represented 25% of the ration dry matter intake. The differences in digestibility of dry matter and protein, due to each of the above three grain mixtures, were not significant, indicating that the cellulose of soybran flakes and dried beet pulp supplemented the silages as well as ground shelled corn. Differences in milk production and body weight changes were not significant. Digestion trials showed the dry matter of the bacitracin treated silage to be significantly more digestible, near the 2.5% level of probability, whereas differences in digestibility of protein were not significant.