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Plant enzymes and protein digestion in ruminants - LS0303

Scientific convention states that it is proteolytic micro-organisms in the rumen which are responsible for breaking down proteins in plant tissue so that they can be used as nutrients by the animal. Recent studies conducted in the Department of Animal Science and Microbiology at IGER show that this concept is wrong and that until now the activity of enzymes inside the ingested plant material has been inadequately considered. How and where protein degradation begins in ruminants are not simply matters of academic interest, but have important implications for the management of ruminant nutrition. For example, current evaluation of the nitrogen (protein) value of feedstuffs are often based on calculation of the rate of release of nitrogen from pre-ground, over-dried plant materials suspended in nylon bags in the rumen. Such methods cannot take account of the effects of nitrogen release from freshly eaten plant matter, from what are essentially dying plant cells. Research in this area is directed to allow the most effective use of indigenous protein resources to improve the efficiency of ruminant production, so as to improve the competitiveness to the industry. In support of the GB grass and clover breeding industry, benefits from this study will include a better definition of the criteria used by plant breeders to select forages with reduced potential for proteolysis on cell death. This will provide better synchrony of protein and energy supply in the rumen, leading to alternative feeding strategies in grazing rummants thereby creating opportunities for milk producers to become more competitive. More efficient nitrogen utilisation will also result in reduced nitrogen losses to the environment.
Project Documents
• Final Report : Plant Enzymes and Protein Digestion in Ruminants   (103k)
• Final Report - Annex : Appendix 1 Figures   (5407k)
Time-Scale and Cost
From: 1997

To: 2002

Cost: £617,810
Contractor / Funded Organisations
Institute of Grassland and Environment Research (IGER)
Livestock Farming              
Peer Review              
Fields of Study