Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-02T22:03:49.405Z Has data issue: false hasContentIssue false

Impact of additional protein on nitrogen retention and amino acid absorption from smallintestine in mature steers fed on grass silage

Published online by Cambridge University Press:  05 November 2021

E.J. Kim
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK Department of Biological and Nutritional Sciences, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK
P.R. Evans
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK
R.T. Evans
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK
D.S. Parker
Affiliation:
Department of Biological and Nutritional Sciences, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK
N.D. Scollan
Affiliation:
Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth SY23 3EB, UK
Get access

Extract

The efficiency of dietary nitrogen use on ruminants fed on forage is poor and this may be largely attributed to an asynchrony between the supply of energy and nitrogen to the rumen microbes, resulting in poor microbial protein synthesis and a low efficiency of utilisation of absorbed amino acid (AA). One of the main factors contributing to the latter is the efficiency of absorption of AA from the small intestine and it has been concluded that a value of 0.75 is appropriate across a range of diets (MacRae and Reeds, 1980). However, it is uncertain how this value may vary on grass silage diets and what effect additional rumen undegradable protein may exert. The objective of this experiment was to measure body nitrogen utilisation and AA absorption from the small intestine in steers fed on grass silage or supplemented with fishmeal.

Type
Programme
Copyright
Copyright © The British Society of Animal Science 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

MacRae, J.C. and Reeds, P.J. 1980. Prediction of protein deposition in ruminants. In Protein deposition in animals (eds. Buttery, P.J. and Lindsay, D.B.), pp. 225249, Butterworths, London.10.1016/B978-0-408-10676-4.50018-5CrossRefGoogle Scholar
Dawson, J.M., Bruce, C.I., Buttery, P.J., Gill, M. and Beever, D.E. 1988. Protein metabolism in the rumen of silage-fed steers–effect of fishmeal supplementation. British Journal of Nutrition. 60. 339353.10.1079/BJN19880104CrossRefGoogle ScholarPubMed