Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T19:47:17.322Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of various low protein diets on the distribution of ruminal nitrogen and on the nitrogen required for maintenance of African sheep

Published online by Cambridge University Press:  02 September 2010

R. C. Elliott  and
J. H. Topps
R. C. Elliott
Affiliation:
Henderson Research Station Mazoe, S. Rhodesia
J. H. Topps
Affiliation:
Department of Agriculture University College of Rhodesia and Nyasaland, Salisbury, S. Rhodesia
Get access

Extract

1. Four groups of diets made up with differing proportions of roughage and concentrates were each given ad lib. to 4 Blackhead Persian wether sheep. The four diets in each group contained approximately 4, 6, 8 and 10% crude protein. The distribution of nitrogen in the rumen at various times after feeding and the nitrogen balance of the sheep were measured.

2. Total N and ammoniacal N content of the rumen liquor were both closely related to the N content of the diet. Diurnal changes in the concentrations of these components were most marked with the diets which had the highest concentration of protein, and consisted of rapid increases after feeding followed by declines later in the day. Each group of diets produced characteristic patterns of change and these changes appeared to be related to the proportion of concentrates in the diet.

3. With sheep given poorly digested veldt grass, very low in protein, levels of ammonia in the rumen were unusually high. This effect was thought t o be due to the recycling of urea and its conversion to ammonia in the rumen.

4. The amounts of digestible N required by the sheep for N equilibrium differed between groups of diets. High apparent requirements of digestible N were associated with relatively high ruminal ammonia levels, but the latter were not considered to be the cause of high requirements.

5. On all groups of diets, sheep were in N equilibrium only when their intakes of total digestible nutrients (TDN) were adequate for maintenance. This indicates that the protein requirement for maintenance was a function of protein content and TDN content of the diet and the effect of these factors on voluntary intake of TDN.

Type
Research Article
Information
Animal Production , Volume 6 , Issue 3 , October 1964 , pp. 345 - 355
Copyright
Copyright © British Society of Animal Science 1964

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

REFERENCES

Annison, E. F., Chalmers, M. I., Marshall, S. B. M. & Synge, R. L. M., 1954. Ruminal ammonia formation in relation to the protein requirement of sheep. III. Ruminal ammonia formation with various diets. J. agric. Sci., 44: 270.CrossRefGoogle Scholar
Blackburn, T. H. & Hobson, P. N., 1960. The degradation of protein in the rumen of the sheep and redistribution of the protein nitrogen after feeding. Brit. J. Nutr., 14: 445.CrossRefGoogle Scholar
Blaxter, K. L., 1962. The Energy Metabolism of Ruminants. Hutchinson. London.Google Scholar
Conway, E. J., 1957. Microdiffusian Analysis and Volumetric Error. 4th edition. Crosby Lockwood and Son, Ltd., London.Google Scholar
Elliott, R. C., 1960. The effects of various levels of supplementary protein on the weight changes in various classes of beef stock on winter veld grazing. Proceedings of the 1st Federal Science Congress, p. 257. Rhodesian Printers, Salisbury.Google Scholar
Elliott, R. C. & Topps, J. H., 1963. Voluntary intake of low protein diets by sheep. Anim. Prod., 5: 269.Google Scholar
Elliott, R. C. & Topps, J. H., 1964. Studies of protein requirements of ruminants. 3. Nitrogen balance trials on Blackhead Persian sheep given diets of different energy and protein content. Brit. J. Nutr., 18: 245.CrossRefGoogle ScholarPubMed
Hobson, P. N., 1963. Rumen microbiology. J. Dairy Res., 30: 288.Google Scholar
Johnson, M. L., 1941. Isolation and properties of a pure yeast polypeptidase. J. biol. Chem., 137: 575.CrossRefGoogle Scholar
Kay, R. N. B., 1963. The physiology of the rumen. J. Dairy Res., 30: 261.CrossRefGoogle Scholar
Moore, W. E. G. & King, K. W., 1958. Determination of the intraruminal distribution of soluble nitrogen. J. Dairy Sci., 41: 1451.CrossRefGoogle Scholar
Smith, P. H., Sweeney, H. C., Rooney, J. R., King, K. W. & Moore, W. E. C., 1956. Stratifications and kinetic changes in the ingesta of the bovine rumen. J. Dairy Sci., 39: 598.CrossRefGoogle Scholar
Somers, M., 1961. Factors influencing the secretion of nitrogen in sheep saliva. 4. The influence of ingested urea on the quantitative recovery of urea in the parotid saliva and the urinary excretions of sheep. Aust. J. exp. biol. med. Sci., 39: 145.CrossRefGoogle Scholar