Protein Systems for Feeding Ruminant Livestock: A European Assessment

The metabolizable protein system for ruminants, published recently in the United Kingdom (Z), was based upon earlier proposals (3, 4). The system includes a number of changes designed to represent the extent of protein degradation in the rumen and the synthesis of microbial protein as variable funct...

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Veröffentlicht in:Journal of dairy science 1994-07, Vol.77 (7), p.2031-2043
Hauptverfasser: Beever, D.E., Cottrill, B.R.
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description The metabolizable protein system for ruminants, published recently in the United Kingdom (Z), was based upon earlier proposals (3, 4). The system includes a number of changes designed to represent the extent of protein degradation in the rumen and the synthesis of microbial protein as variable functions. The system also provides a more rational description of the energy available for microbial growth (fermentable metabolizable energy) by discounting the energy content of dietary lipids and fermentation end products (silages), which are considered to make a relatively insignificant contribution or none to microbial metabolism. The assessment of availability of undegraded dietary protein in the small intestine is revised also, and variable efficiencies of utilization of absorbed AA in relation to the nature of the synthetic process (e.g., meat and milk) are proposed. This paper considers these changes and assesses the adequacy of current laboratory techniques for determining the protein value of feedstuffs for ruminants. A number of conceptual and technical problems are identified, and ways of overcoming them are discussed. We conclude that such systems must be used in practice with guarded enthusiasm and suggest that mechanistic models, which provide a more appropriate representation of the biological processes, be encouraged as the basis of the next generation of feeding systems.
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Collagen ; Nutritive Value ; piensos ; prise alimentaire homme ; protein degradability ; proteinas ; proteine ; proteins ; reino unido ; royaume uni ; rumen ; Rumen - metabolism ; Rumen - microbiology ; rumen microorganisms ; rumiante ; ruminant ; ruminants ; Ruminants - physiology ; technique de prevision ; tecnicas de prediccion ; united kingdom ; Vertebrates: anatomy and physiology, studies on body, several organs or systems</subject><ispartof>Journal of dairy science, 1994-07, Vol.77 (7), p.2031-2043</ispartof><rights>1994 American Dairy Science Association</rights><rights>1995 INIST-CNRS</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c4494-56f6151c1d62737167c166d9ef4a3d56f0a273cf13fdc75a388826b2b76964873</citedby><cites>FETCH-LOGICAL-c4494-56f6151c1d62737167c166d9ef4a3d56f0a273cf13fdc75a388826b2b76964873</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://dx.doi.org/10.3168/jds.S0022-0302(94)77148-4$$EHTML$$P50$$Gelsevier$$Hfree_for_read</linktohtml><link.rule.ids>314,780,784,3550,27869,27924,27925,45995</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&amp;idt=3315765$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/7929963$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Beever, D.E.</creatorcontrib><creatorcontrib>Cottrill, B.R.</creatorcontrib><creatorcontrib>Philippines Univ., Los Banos, College, Laguna (Philippines)</creatorcontrib><title>Protein Systems for Feeding Ruminant Livestock: A European Assessment</title><title>Journal of dairy science</title><addtitle>J Dairy Sci</addtitle><description>The metabolizable protein system for ruminants, published recently in the United Kingdom (Z), was based upon earlier proposals (3, 4). 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We conclude that such systems must be used in practice with guarded enthusiasm and suggest that mechanistic models, which provide a more appropriate representation of the biological processes, be encouraged as the basis of the next generation of feeding systems.</description><subject>aliment pour animaux</subject><subject>Animal Feed</subject><subject>Animals</subject><subject>Biological and medical sciences</subject><subject>Dietary Proteins - administration &amp; dosage</subject><subject>Dietary Proteins - metabolism</subject><subject>digestibilidad</subject><subject>digestibilite</subject><subject>digestibility</subject><subject>Digestion</subject><subject>Europe</subject><subject>evaluacion</subject><subject>evaluation</subject><subject>feeds</subject><subject>fermentable metabolizable energy</subject><subject>food intake</subject><subject>forecasting</subject><subject>Fundamental and applied biological sciences. 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subjects aliment pour animaux
Animal Feed
Animals
Biological and medical sciences
Dietary Proteins - administration & dosage
Dietary Proteins - metabolism
digestibilidad
digestibilite
digestibility
Digestion
Europe
evaluacion
evaluation
feeds
fermentable metabolizable energy
food intake
forecasting
Fundamental and applied biological sciences. Psychology
ingestion de alimentos
madurez
maturite
maturity
Metabolisms and neurohumoral controls
metabolizable protein
microbial protein synthesis
microorganisme du rumen
microorganismos del rumen
Nitrogen metabolism. Proteins. Glycoproteins. Nucleic acids. Collagen
Nutritive Value
piensos
prise alimentaire homme
protein degradability
proteinas
proteine
proteins
reino unido
royaume uni
rumen
Rumen - metabolism
Rumen - microbiology
rumen microorganisms
rumiante
ruminant
ruminants
Ruminants - physiology
technique de prevision
tecnicas de prediccion
united kingdom
Vertebrates: anatomy and physiology, studies on body, several organs or systems
title Protein Systems for Feeding Ruminant Livestock: A European Assessment
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