Information on plant carbohydrate polymers and microbial metabolism of feed carbohydrate is presented together with information on the use of microbial metabolic end products by the host ruminant.  Agribusiness interventions and metabolic diseases of ruminants related to energy metabolism are also addressed.

Descriptions of pathways of microbial metabolism in the reticulo-rumen in this teaching unit are not exhaustively comprehensive. The pathways for synthesis of some microbial metabolic products such as valerate, isovalerate and isobutyrate are not examined and the metabolic profiles of only selected species of microorganisms are presented. The roles of fungi and of protozoa are not addressed. The emphasis is on providing enough material to allow essential understanding of the importance of microbial metabolism as it relates to energy metabolism of the host ruminant.

This CAL can be browsed in the sequence presented by paging down or used as a research tool to answer the test bank questions.  A selection of these questions will appear in the end of semester examination.  References are given to library resources for further study.

Links to sites within this CAL are shown in green text.  Words entered in the glossary are shown in blue. The Glossary will open in a separate window.

After studying this material you should:

• understand the different ways in which various bacterial species use diverse nutrients available in the reticulo-rumen to support their growth.
• understand the different methods they use to generate ATP.
• understand the reasons for the differences in energy metabolism under aerobic and anaerobic conditions.
• understand some of the metabolic pathways by which many of the products of microbial metabolism are used by the host ruminant.
• understand the basis for agribusiness interventions designed to reduce methanogenesis.
• understand aspects of a number of metabolic diseases encountered with ruminant animals