Hostname: page-component-848d4c4894-hfldf Total loading time: 0 Render date: 2024-05-21T04:20:12.480Z Has data issue: false hasContentIssue false
  • English
  • Français

Incorporation of nitrogen into rumen bacterial fractions of steers given protein- and urea-containing diets. Ammonia assimilation into intracellular bacterial amino acids

Published online by Cambridge University Press:  24 July 2007

J. S. Blake ,
D. N. Salter  and
R. H. Smith
J. S. Blake
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, BerkshireRG2 9AT
D. N. Salter
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, BerkshireRG2 9AT
R. H. Smith
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, BerkshireRG2 9AT
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. Experiments were carried out in vivo to investigate the pathways of ammonia incorporation into rumen bacteria, bacterial fractions and free amino acids within the bacteria.

2. Steers were alternately given two isoenergetic, isonitrogenous diets containing the nitrogen mainly as either urea or decorticated groundnut meal (DCGM). At the end of each period on a given diet, a solution of 15NH4Cl was infused into the rumen and samples of rumen contents were removed at 2, 10, 20 and 90 min and 5, 10 and 24 h afterwards. Concentrations of ammonia and its 15N enrichment were determined and samples of mixed rumen bacteria were prepared. Bacteria were disrupted ultrasonically and separated into bacterial protein, cell wall and protein-free cell supernatant fractions. Amino acids were separated after hydrolysis and their 15N contents determined.

3. A rumen fluid circulation pump was developed so that representative samples could be taken at very short time intervals after the introduction of the 15N label.

4. Rumen pH changes, rumen fluid dilution rates and patterns of rumen ammonia concentrations were consistent with normal rumen metabolism. Net bacterial synthesis (as calculated from the net outflow of bacteria from the rumen) was significantly (P < 0·05) greater with the DCGM diet (12·4 g bacterial N/d) than with the ureadiet (9·24 g bacterial N/d).

5. With both diets the 15N label rapidly left the rumen ammonia pool and entered the rumen bacteria. Analysis of the bacterial fractions indicated that the label appeared rapidly in the protein-free cell supernatant fraction and more slowly in the bacterial protein and cell wall fractions.

6. With the DCGM diet bacteria apparently utilized intracellular label less efficiently than with the urea diet. The proportion of N in the protein-free cell supernatant was higher with the DCGM diet, suggesting increased levels of intracellular amino acids and peptides, following extracellular protein degradation.

7. Levels of enrichment of the amino acids alanine and glutamate in the protein-free cell supernatant fraction suggested that the enzymes alanine dehydrogenase (EC 1. 4. 1. 1) and glutamate dehydrogenase (EC 1. 4. 1. 2 and 1. 4. 1. 4) may be the major enzymes for assimilating ammonia when concentrations of soluble carbohydrate and rumen ammonia are high in the rumen.

8. The high levels of intracellular alanine are discussed with reference to publishedwork on the excretion of alanine by rumen bacteria.

Type
Research Article
Information
British Journal of Nutrition , Volume 50 , Issue 3 , November 1983 , pp. 769 - 782
Copyright
Copyright © The Nutrition Society 1983

References

Allison, M. J. (1969). Journal of Animal Science 29, 797–807.CrossRefGoogle Scholar
Benson, J. V. Jr, Gordon, M. J. & Patterson, J. A. (1967). Analytical Biochemistry 18, 228–240.CrossRefGoogle Scholar
Blackburn, T. H. & Hobson, P. N. (1960). Journal of General Microbiology 22, 290–294.CrossRefGoogle Scholar
Blackburn, T. H. & Hullah, W. A. (1974). Canadian Journal of Microbiology 20, 435–441.CrossRefGoogle Scholar
Blake, J. S., Salter, D. N. & Smith, R. H. (1981). Proceedings of the Nutrition Society 40, 3A.Google Scholar
Byrant, M. P. (1973). Federation Proceedings 32, 1809–1813.Google Scholar
Bryant, M. P. & Robinson, I. M. (1962). Journal of Bacteriology 84, 605–614.CrossRefGoogle Scholar
Burchall, J. J., Reichelt, E. C. & Wolin, M. J. (1964). Journal of Biological Chemistry 239, 1794–1798.CrossRefGoogle Scholar
Cole, N. A., Johnson, R. R., Owens, F. N. & Males, J. R. (1976). Journal of Animal Science 43, 497–503.CrossRefGoogle Scholar
Erfle, J. D., Sauer, F. D. & Mahadevan, S. (1977). Journal of Dairy Science 60, 1064–1072.CrossRefGoogle Scholar
Florence, E. & Milner, D. F. (1979). Analyst, London 104, 378–381.CrossRefGoogle Scholar
Goulden, J. D. S. & Salter, D. N. (1979 a). Journal of Chromatography 179, 179–178.CrossRefGoogle Scholar
Goulden, J. D. S. & Salter, D. N. (1979 b). Analyst, London 104, 756–765.CrossRefGoogle Scholar
Harrison, D. G., Beever, D. E., Thompson, D. J. & Osbourn, D. F. (1975). Journal of Agricultural Science, Cambridge 85, 93–101.CrossRefGoogle Scholar
Hume, I. D. (1970). Australian Journal of Agricultural Research 21, 305–314.CrossRefGoogle Scholar
Jenkinson, H. F., Buttery, P. J. & Lewis, D. (1979). Journal of General Microbiology 113, 305–313.CrossRefGoogle Scholar
Joyner, A. E. & Baldwin, R. L. (1966). Journal of Bacteriology 92, 1321–1330.CrossRefGoogle Scholar
Lewis, D. (1955). British Journal of Nutrition 9, 215–230.CrossRefGoogle Scholar
Lloyd-Jones, C. P., Adam, J. S., Hudd, G. A. & Hill-Cottingham, D. G. (1977). Analyst, London 102, 473–476.CrossRefGoogle Scholar
McDonald, I. W. (1952). Biochemical Journal 51, 86–90.CrossRefGoogle Scholar
Mathison, G. W. & Milligan, L. P. (1971). British Journal of Nutrition 25, 351–366.CrossRefGoogle Scholar
Nolan, J. V. & Leng, R. A. (1972). British Journal of Nutrition 27, 177–194.CrossRefGoogle Scholar
Pittman, K. A., Lakshmanans, S. & Bryant, M. P. (1967). Journal of Bacteriology 93, 1499–1508.CrossRefGoogle Scholar
Prigge, E. C., Galyean, M. L., Owens, F. N., Wagner, D. G. & Johnson, R. R. (1978). Journal of Animal Science 46, 249–254.CrossRefGoogle Scholar
Prins, R. A., Mal-Van Gestal, J. C. & Counott, G. H. M. (1979). Zeitschrift Tierphysiologie Tierernahrung und Futtermittelkunde 42, 333–339.CrossRefGoogle Scholar
Salter, D. N., Daneshvar, K. & Smith, R. H. (1979). British Journal of Nutrition 41, 197–209.CrossRefGoogle Scholar
Salter, D. N. & Smith, R. H. (1977). British Journal of Nutrition 38, 207–216.CrossRefGoogle Scholar
Shimbayashi, K., Obara, Y. & Yonemura, Y. (1975). Japanese Journal of Zootechnical Science 46, 243–250.Google Scholar
Shishkina, V. N. & Trotsenko, Y. A. (1979). Federation of European Microbiological Societies—Microbiology Letters 5, 187–191.CrossRefGoogle Scholar
Smith, C. J., Bryant, M. P. & Hespell, R. B. (1978). Abstract of the Annual Meeting—American Society of Microbiology 78, K14.Google Scholar
Smith, R. H. (1962). Biochemical Journal 83, 151–163.CrossRefGoogle Scholar
Stevenson, I. L. (1978). Canadian Journal of Microbiology 24, 1236–1241.CrossRefGoogle Scholar
Sutherland, T. M., Ellis, W. C., Reid, R. S. & Murray, M. G. (1962). British Journal of Nutrition 16, 603–614.CrossRefGoogle Scholar
Syvaoja, E. L. & Kreula, M. (1979). Journal of the Scientific Agricultural Society of Finland 51, 497–505.Google Scholar
Wallace, R. J. & Henderson, C. (1978). Proceedings of the Society for General Microbiology 5, 102 (Abstr).Google Scholar
Warner, A. C. I. (1956). Journal of General Microbiology 28, 129–146.CrossRefGoogle Scholar