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Efficiency of utilization of absorbed amino acids in growing lambs given forage and forage: barley diets

Published online by Cambridge University Press:  02 September 2010

J. C. MacRae
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
L. A. Bruce
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
D. S. Brown
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
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Abstract

The efficiency of utilization of absorbed essential amino acids (AA) was studied in wether lambs (35 to 40 kg live weight) given dried grass and dried grass: barley pelleted diets over an intake range from maintenance (M) to 2·5 M energy intake. Each animal was prepared with a duodenal and Heal simple (T-shaped) cannulafor the collection of digesta entering and leaving the small intestine and with a catheter into the abomasum for the infusion of digesta phase markers (103Ru phenanthroline and 51 Cr ethylene diamine tetra acetic acid). The efficiencies of utilization of total AA and individual essential AA (EAA) were calculated from the ratios of the regressions describing AA retention per unit nitrogen (N) intake (assessed using the N retention data obtained in the present study and the AA composition of N retention derived during an accompanying comparative slaughter experiment) and AA absorption per unit N intake. These ratios for total EAA were 0·5 for the grass diet and 0·59 for the grass plus barley diet. Values for individual EAA ranged from 0·32 for threonine in sheep given the grass diet to 0·88 for arginine in sheep given the grass: barley diet. Whilst the ratios for total and individual EAA were generally higher for the grass: barley diet the very wide 95% confidence limits associated with these derived values make any between-diet or between-EAA comparisons equivocal. The data appear to support the introduction by the Agricultural and Food Research Council (1992), of a scaling factor to reduce the high efficiency of utilization of AA used previously.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1995

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References

Agricultural and Food Research Council. 1984. The nutrient requirements of ruminant livestock. Supplement No. 1. Report of the Protein Group of the ARC Working Party, Commonwealth Agricultural Bureaux, Farnham Royal.Google Scholar
Agricultural and Food Research Council. 1992. Technical Committee on responses to nutrients. Report no. 9. Nutritive requirements of ruminant animals: protein. Nutrition Abstracts and Reviews, Series B 62: 787835.Google Scholar
Agricultural Research Council. 1980. The nutrient requirements of ruminant livestock. Commonwealth Agricultural Bureaux, Farnham Royal.Google Scholar
Binnerts, W. T., Klooster A. Th., van't and Frens, A. M. 1968. Soluble chromium indicator measured by atomic absorption in digestion experiments. Veterinary Record 82: 470.Google Scholar
Clark, J. H. 1975. Lactational responses to post-ruminal administratin of proteins. Journal of Dairy Science 50: 16211625.Google Scholar
Coelho da Silva, J. F., Seeley, R. C., Beever, D. E., Prestcott, J. H. D. and Armstrong, D. G. 1972. The effect in sheep of physical form and stage of growth on the sites of digestion of dried grass. 2. Sites of nitrogen digestion. British Journal of Nutrition 28: 357371.CrossRefGoogle Scholar
Davidson, J., Mathieson, J. and Boyne, A. W. 1970. The use of automation in determining nitrogen by the Kjeldahl method, with final calculations by computer. Analyst, London 95: 181193.CrossRefGoogle ScholarPubMed
Faichney, G. J. 1975. The use of markers to partition digestion within the gastrointestinal tract or ruminants. In Digestion and metabolism in the ruminant (ed. McDonald, I. W. and Warner, A. C. I.), pp. 277291. University of New England Publishing Unit, Armidale.Google Scholar
Genstat 5 Committee. 1987. Genstat 5 reference manual. Clarendon Press, Oxford.Google Scholar
Hecker, J. F. 1974. Experimental surgery on small ruminants. Butterworths, London.Google Scholar
MacRae, J. C. and Lobley, G. E. 1982. Some factors influencing thermal energy losses during the metabolism of ruminants. Livestock Production Science 9: 447456.CrossRefGoogle Scholar
MacRae, J. C. and Lobley, G. E. 1986. Interactions between energy and protein. In Control of digesta metabolism in ruminants, (ed. Milligan, L. P., Grovum, W. L. and Dobson, A.), pp. 367385. Prentice Hall, Englewood Cliffs, NJ.Google Scholar
MacRae, J. C. and Reeds, P. J. 1980. Prediction of protein deposition in ruminants. In Protein deposition in animals (ed. Buttery, P. J. and Lindsay, D. B.), pp. 225249. Butterworths, London.CrossRefGoogle Scholar
MacRae, J. C., Smith, J. S., Dewey, P. J. S., Brewer, A. C., Brown, D. S. and Walker, A. 1985. The efficiency of utilisation of metabolisable energy and apparent absorption of amino acids in sheep given spring and autumn harvested dried grass. British Journal of Nutrition 54: 197209.CrossRefGoogle Scholar
MacRae, J. C. and Ulyatt, M. J. 1974. Quantitative digestion of fresh herbage by sheep. 2. The sites of digestion of some nitrogenous constituents. Journal of Agricultural Science, Cambridge 82: 309319.CrossRefGoogle Scholar
MacRae, J. C., Walker, A., Brown, D. and Lobley, G. E. 1993. Accretion of total protein and individual amino acids by organs and tissues of growing lambs and the ability of nitrogen balance techniques to quantitate protein retention. Animal Production 57: 237245.Google Scholar
Moore, S. 1962. On the determination of cystine as cysteic acid. Journal of Biological Chemistry 238: 235.CrossRefGoogle Scholar
Ranawana, S. S. E. and Kellaway, R. C. 1977. Responses to post-ruminal infusion of glucose and casein in lactating goats. British Journal of Nutrition 37: 395402.CrossRefGoogle Scholar
Rowett Research Institute. 1975. Feedingstuffs Evaluation Unit first report. Department of Agriculture and Fisheries for Scotland.Google Scholar
Spiers, H. R., Clark, J. H., Derrig, R. G. and Davis, C. L. 1975. Milk production and nitrogen utilisation in response to post-ruminal infusion of sodium caseinate in lactating cows. Journal of Nutrition 105: 11111121.CrossRefGoogle Scholar
Storm, E. and Ørskov, E. R. 1984. The nutritive value of rumen microorganisms in ruminants. 4. The limiting amino acids of microbial protein in growing sheep determined by a new approach. British Journal of Nutrition 62: 613620.CrossRefGoogle Scholar
Tan, T. N., Weston, R. H. and Hogan, J. P. 1971. Use of 103Ru phenanthroline as a marker in digestion studies with sheep. International Journal of Applied Radiation and Isotopes 22: 301308.CrossRefGoogle ScholarPubMed
Whitelaw, F. G., Milne, J. S., Ørskov, E. R. and Smith, J. S. 1986. The nitrogen and energy metabolism of lactating cows given abomasal infusions of casein. British Journal of Nutrition 55: 537556.CrossRefGoogle ScholarPubMed