Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Animal Science


In the past several years, there has been increased interest in what has been referred to by some as the two-phase feeding of ruminants. This includes backgrounding, when animals are fed diets high in roughage during a growing period, followed by high-grain feeding during a relatively short finishing period. An interim period of grain adaptation, usually 2 to 3 weeks in length, is necessary in this feeding system to avoid the deleterious effects of the rumen acidosis associated with abrupt changes from predominantly roughage diets to high-grain diets. Feedlot performance during this adaptation phase is generally lower than desired. The feeding of low levels of alkaline materials and other inorganic mineral substances such as bentonite has shown some benefit in the past in maintaining normal gains during abbreviated adaptation periods. The objectives of the experiments reported herein were to: 1. Evaluate various materials in terms of protection that they may provide from rumen acidosis associated with an abrupt change in diets, 2 to combine sodium bentonite and sodium bicarbonate to determine if there are possible synergistic actions, and 3 to determine effects of these materials on overall performance when fed to ruminants throughout the feeding period.

Library of Congress Subject Headings

Ruminants -- Feeding and feeds

Minerals in animal nutrition




Number of Pages



South Dakota State University