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Nitrogen and carbon flows between the caecum, blood and rumen in sheep given chopped lucerne (Medicago sativa) hay

Published online by Cambridge University Press:  09 March 2007

R. M. Dixon  and
J. V. Nolan
R. M. Dixon
Affiliation:
Department of Biochemistry and Nutrition, Faculty of Rural Science, University of New England, Armidale, NSW 2351, Australia
J. V. Nolan
Affiliation:
Department of Biochemistry and Nutrition, Faculty of Rural Science, University of New England, Armidale, NSW 2351, Australia
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Abstract

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1. Experiments involving 15N and 14C tracers were made in sheep consuming 800 g air-dry chopped lucerne (Merlicugo sativa) hay/d and providing 20.4 g N/d to study N and C flows within the caecal digesta and between the caecum, blood and rumen.

2. Continuous infusions of 15N tracers were made into the caecal ammonia, blood urea and rumen NH3 pools. The concentration and enrichment of caecal digesta NH3-N, caecal microbial N, caecal digesta non-urea. non-ammonia-N (NU-NAN), faecal NU-NAN, blood urea-N, rumen digesta NH3-N and rumen bacterial N were estimated at intervals during the infusions. A three-pool open-compartment model was solved to estimate N flows between the caecal digesta NH3-N, blood urea-N and rumen digesta NH3-N pools.

3. The rate of irreversible loss from the caecal digesta NH3-N pool was 2.17 (SE 0.623) g N/d. On average 0.9 (SE 0.56) g N/d of caecal digesta NH3-N was derived from blood urea and 0.1 (SE 0.08) g caecal digesta NH3-N/d was apparently derived from the fermentation of undigested rumen microbes in the caecum. The amount of NH3-N produced by proteolysis and deamination of dietary and endogenous N was 1.1 (SE 0.13) g/d.

4. There was net incorporation of 0.56 (SE 0.306) g caecal digesta NH3-N/d into caecal microbes. The microbial U synthesized de novo in the caecum was not determined, but 2.9 (SE 0.52) g microbial N/d of both rumen and caecal origin flowed out of the caecum and constituted 0.48 of the NU-NAN flow. The majority (mean 0.83 (SE 0.044)) of this microbial N was excreted in faeces.

5. On average 1.8 (SE 0.80) g caecal digesta NH3-N/d were absorbed. Of this NH3-N, 0.92 (SE 0.054) was converted to blood urea, contributing 0.10 (SE 0.031) of blood urea-N. Only 0.012 (SE 0.0041) of rumen digesta NH3-N and 0.005 (SE 0, 0009) of rumen bacterial N were derived from caecal digesta NH3-N.

6. Infusions of 14C tracers were made into the caecal digesta bicarbonate, blood bicarbonate, rumen digesta bicarbonate and blood urea pools, and samples were obtained at intervals to determine the specific radioactivity of each pool. A four-pool open-compartment model was solved to estimate C flows between these pools.

7. The rate of irreversible loss of blood urea estimated with [14C]urea (17.1 (SE 1.18) g N/d) was greater (P < 0.01) than that estimated with [15N]urea (14.0 (SE 0.87) g N/d).

8. Transfer of blood urea to the caecal digesta estimated with 14C tracers (1.4 (SE 0.61) g N/d) was greater (P < 0.01) than that estimated with I5N tracers (0.9 (SE 0.56) g N/d). The estimate of transfer of blood urea to the rumen digesta was also greater with 14C tracers (P < 0.05; 1.7 (SE 0.15) and 1.2 (SE 0.19) g N/d respectively). The urea hydrolysed in the gastrointestinal tract other than in the rumen digesta pool and the caecal digesta pool was 0.56 of total urea hydrolysis when estimated with 14C tracers, or 0.69 when estimated with 15N tracers. Results from previous acute experiments suggested that with three of the four observations made in three sheep in the present experiment the transfer of blood urea to the caecal digesta could have occurred entirely via ileal digesta. Similarly, urea transfer to the rumen digesta could have occurred entirely via saliva.

Type
Papers on General Nutrition
Information
British Journal of Nutrition , Volume 55 , Issue 2 , March 1986 , pp. 313 - 332
Copyright
Copyright © The Nutrition Society 1986

References

REFERENCES

Allen, A. & Miller, E. L. (1976). British Journal of Nutrition 36, 353–368.CrossRefGoogle Scholar
Association of Official Analytical Chemists (1975). Official Methods of Analysis 12th ed. Washington, DC: AOAC.Google Scholar
Beever, D. E., Thompson, D. J. & Cammell, S. B. (1976). Journal of Agricultura1 Science, Cambridge 86, 443–452.CrossRefGoogle Scholar
Billich, C. O. & Levitan, R. J. (1969). Journal of Clinical Investigation 48, 1336–1347.CrossRefGoogle Scholar
Binnerts, W. T., Van't Klooster, A. T. & Frens, A. M. (1968). Veterinary Record 82, 470.Google Scholar
Boda, K., Varady, J. & Havassy, I. (1976). Tracer Studies on Non-Protein Nitrogen for Ruminants, vol. 3, pp. 1–12, Vienna: International Atomic Energy Agency.Google Scholar
Chalmers, M. I., Grant, I. & White, F. (1976). In Protein Metabolism and Nutrition, pp. 159–179 [Cole, D. J. A., Boorman, K. N., Buttery, P. J., Lewis, D., Neale, R. J. and Swan, H., editors]. London: Butterworths.Google Scholar
Cheng, K.-J. & Wallace, R. J. (1979). British Journal of Nutrition 42, 553–557.CrossRefGoogle Scholar
Cocimano, M. R. & Leng, R. A. (1967). British Journal of Nutrition 21, 353–371.CrossRefGoogle Scholar
Coelho da Silva, J. F., Seeley, R. C., Beever, D. E., Prescott, J. H. D. & Armstrong, D. G. (1972 a). British Journal of Nutrition 28, 357–371.CrossRefGoogle Scholar
Coelho da Silva, J. F., Seeley, R. C., Thomson, D. J., Beever, D. E. & Armstrong, D. G. (1972 b). British Journal of Nutrition 28, 43–61.CrossRefGoogle Scholar
Dixon, R. M. & Milligan, L. P. (1984). Canadian Journal of Animal Science 64, 103–111.CrossRefGoogle Scholar
Dixon, R. M. & Nolan, J. V. (1982). British Journal of Nutrition 47, 289–300.CrossRefGoogle Scholar
Dixon, R. M. & Nolan, J. V. (1983). British Journal of Nutrition 50, 757–768.CrossRefGoogle Scholar
Dixon, R. M., Nolan, J. V. & Milligan, L. P. (1982). British Journal of Nutrition 47, 301–309.CrossRefGoogle Scholar
Engelhardt, W. v. & Hinderer, S. (1976). Tracer Studies on Non-Protein Nitrogen for Ruminants, vol. 2, pp. 57–58. Vienna: International Atomic Energy Agency.Google Scholar
Hakim, A. A. & Lipson, N. (1964). American Journal of Physiology 206, 1315–1320.CrossRefGoogle Scholar
Harrison, D. G., Beever, D. E. & Thompson, D. J. (1971). Proceedings of the Nutrition Society 30, 16A.Google Scholar
Hecker, J. F. (1969). Australian Veterinary Journal 45, 293–294.CrossRefGoogle Scholar
Hecker, J. F. (1971 a). British Journal of Nutrition 25, 85–89.CrossRefGoogle Scholar
Hecker, J. F. (1971 b). British Journal of Nutrition 26, 135–145.CrossRefGoogle Scholar
Hecker, J. F. (1973). Journal of Agricultural Science, Cambridge 80, 63–69.CrossRefGoogle Scholar
Hogan, J. P. (1973). Australian Journal of Agricultural Research 24, 587–598.CrossRefGoogle Scholar
Hoover, W. H. (1978). Journal of Animal Science 46, 1789–1799.CrossRefGoogle Scholar
Houpt, T. R. (1970). In Physiology of Digestion and Metabolism in the Ruminant, pp. 119–131 [Phillipson, A. T., editor]. Newcastle upon Tyne: Oriel Press.Google Scholar
Judson, G. J., Abdelsamie, R. & Bird, R. P. (1975). Australian Journal of Agricultural Research 26, 743–749.CrossRefGoogle Scholar
Kennedy, P. M. (1980). British Journal of Nutrition 43, 125–140.CrossRefGoogle Scholar
Kennedy, P. M. & Milligan, L. P. (1977). Proceedings of the Nutrition Society 36, 53A.Google Scholar
Kennedy, P. M. & Milligan, L. P. (1980). Canadian Journal of Animal Science 60, 205–221.CrossRefGoogle Scholar
Kornberg, H. L. & Davies, R. E. (1955). Physiological Reviews 35, 169–177.CrossRefGoogle Scholar
Kornberg, H. L., Davies, R. E. & Wood, D. R. (1954). Biochemical Journal 56, 355–363.CrossRefGoogle Scholar
Leng, R. A. & Leonard, G. J. (1965). British Journal of Nutrition 19, 469–484.CrossRefGoogle Scholar
MacRae, J. C., Reid, C. S. W., Dellow, D. W. & Wyburn, R. S. (1973). Research in Veterinary Science 14, 78–85.CrossRefGoogle Scholar
MacRae, J. C. & Ulyatt, M. J. (1974). Journal of Agricultural Science, Cambridge 82, 309–319.CrossRefGoogle Scholar
Maeng, W. J., Van Nevel, C. J., Baldwin, R. L. & Morris, J. G. (1976). Journal of Dairy Science 59, 68–78.CrossRefGoogle Scholar
Mann, J. & Gurpide, E. (1966). Journal of Clinical Endocrinology and Metabolism 26, 1346–1354.CrossRefGoogle Scholar
Mason, V. C. & Milne, G. (1971). Journal of Agricultural Science, Cambridge 77, 99–101.CrossRefGoogle Scholar
Mason, V. C. & White, F. (1971). Journal of Agricultural Science, Cambridge 77, 91–98.CrossRefGoogle Scholar
Mossberg, S. M. & Ross, G. (1967). Journal of Clinical Investigation 46, 490–498.CrossRefGoogle Scholar
Nolan, J. V. & Leng, R. A. (1970). British Journal of Nutrition 24, 905–915.CrossRefGoogle Scholar
Nolan, J. V. & Leng, R. A. (1972). British Journal of Nutrition 27, 177–194.CrossRefGoogle Scholar
Nolan, J. V. & Leng, R. A. (1974). Proceedings of the Nutrition Society 33, 1–8.CrossRefGoogle Scholar
Nolan, J. V., Norton, B. W. & Leng, R. A. (1976). British Journal of Nutrition 35, 137–147.CrossRefGoogle Scholar
Nolan, J. V. & Rowe, J. B. (1976). In Reviews in Rural Science, vol. 2 pp. 151–159 [Sutherland, T. M., McWilliam, J. R. and Leng, R. A., editors]. Armidale, Australia: University of New England Publishing Unit.Google Scholar
Nolan, J. V. & Stachiw, S. (1979). British Journal of Nutrition 42, 63–80.CrossRefGoogle Scholar
Norton, B. W., Jones, A. N. & Armstrong, D. G. (1982). British Journal of Nutrition 48, 26–274.Google Scholar
Norton, B. W., Murray, R. M., Entwistle, K. W., Nolan, J. V., Ball, F. M. & Leng, R. A. (1978). Australian Journal of Agricultural Research 29 595–603.CrossRefGoogle Scholar
Salter, D. N., Daneshvar, K. & Smith, R. H. (1979). British Journal of Nutrition 41, 197–209.CrossRefGoogle Scholar
Shipley, R. A. & Clark, R. E. (1972). Tracer Methods for In Vivo Kinetics. New York and London: Academic Press.Google Scholar
Snedecor, G. W. & Cochran, W. G. (1967). Statistical Methods, 6th ed. Ames, Iowa, USA: Iowa State University Press.Google Scholar
Ulyatt, M. J., Dellow, D. W., Reid, C.S. W. & Bauchop, T. (1975). In Digestion and Metabolism in the Ruminant, pp. 119–133 [McDonald, I. W. and Warner, A. C. I., editors]. Annidale, Australia: University of New England Publishing Unit.Google Scholar
Wolpert, E., Phillips, S. F. & Summerskill, W. H. J. (1971). Lancet ii 1387–1390.CrossRefGoogle Scholar