Hostname: page-component-848d4c4894-v5vhk Total loading time: 0 Render date: 2024-07-02T00:18:51.927Z Has data issue: false hasContentIssue false
  • English
  • Français

The indirect estimation of the digestibility of pasture herbage I. Nitrogen and chromogen as faecal index substances

Published online by Cambridge University Press:  27 March 2009

J. F. D. Greenhalgh  and
J. L. Corbett
J. F. D. Greenhalgh
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen
J. L. Corbett
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen
Get access Rights & Permissions [Opens in a new window]

Extract

1. In seventeen digestibility trials carried out between May and November, 1957, groups of three steers were fed on fresh herbage, cut mainly from mixed swards. Herbage digestibility and the concentrations in faeces of the index substances nitrogen and chromogen were measured over periods of 5 days. Organic matter digestibility ranged from 61·2 to 78·9%.

2. The relationship between herbage digestibility and faecal nitrogen concentration could not be described satisfactorily by a single regression equation for all trials, and separate equations were calculated for (a) first-growth herbage and (b) aftermath (second and third growths). For a given faecal nitrogen concentration herbage digestibility was about five units higher for first-growth than for aftermath herbage.

3. For the faecalchromogen-digestibilityrelationship the difference between growths was even greater and, again, two equations were required. In most trials the quantity of chromogen excreted was apparently greater than the quantity consumed.

4. The ‘seasonal’ differences in faecal index relationships were caused by the fact that later growths of herbage contained considerably greater concentrations of nitrogen and chromogen than did firstgrowth herbage of the same digestibility. There was also some evidence that the relationships may be affected by the application of nitrogenous fertilizers to the sward.

5. In order to avoid biases in the indirect estimation of herbage digestibility it appears important to use different regressions for different growths. Although such regressions would be restricted in their application they are likely to be more precise than general equations. In these trials both nitrogen and chromogen regressions had low residual standard deviations of ± 1·5 units of digestibility.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 55 , Issue 3 , December 1960 , pp. 371 - 376
Copyright
Copyright © Cambridge University Press 1960

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

Balch, C. C., Bartlett, S. & Johnson, V. W. (1951). J. Agric. Sci. 41, 98.CrossRefGoogle Scholar
Blaxter, K. L. & Mitchell, H. H. (1948). J. Anim. Sci. 7, 351.CrossRefGoogle Scholar
Deijs, W. B. & Bosman, M. S. M. (1955). Rec. Trav. chim. Pays-Bas, 74, 1207.CrossRefGoogle Scholar
Forbes, R. M. & Garrigus, W. P. (1948). J. Anim. Sci. 7, 373.CrossRefGoogle Scholar
Garrigus, W. P. (1934). Proc. Amer. Soc. Anim. Prod. p. 66.Google Scholar
Harberts, C. L., Immink, H. J. & Deijs, W. B. (1955). Versl. Inst. Landb. Onderz., Wageningen, over 1954, p. 228.Google Scholar
Hardison, W. A., Reid, J. T., Marten, C. M. & Woolfolk, P. G. (1954). J. Dairy Sci. 37, 89.CrossRefGoogle Scholar
Holmes, W. (1949). J. Agric. Sci. 39, 128.CrossRefGoogle Scholar
Kane, E. A., Jacobson, W. C., Ely, R. E. & Moore, L. A. (1953). J. Dairy Sci. 36, 637.CrossRefGoogle Scholar
Kennedy, W. K. & Lancaster, R. J. (1957). Proc. N.Z. Soc. Anim. Prod. 17, 56.Google Scholar
Lancaster, R. J. (1949). Nature, Lond., 163, 330.CrossRefGoogle Scholar
Lancaster, R. J. (1950). Proc. N.Z. Soc. Anim. Prod. 10, 45.Google Scholar
Lancaster, R. J. (1954). N.Z. J. Sci. Tech. A, 36, 15.Google Scholar
Lancaster, R. J. & Bartrum, M. P. (1954). N.Z. J. Sci. Tech. A, 35, 489.Google Scholar
Minson, D. J. & Raymond, W. F. (1958). Exp. Grassl. Res. Inst. Hurley, 10, 92.Google Scholar
Raven, A. M. & Robinson, K. L. (1957). Res. exp. Rec. Minist. Agric. N. Ireland 5, 62.Google Scholar
Raymond, W. F. (1948). Nature, Lond., 161, 937.CrossRefGoogle Scholar
Raymond, W. F., Eyles, D. E. & Caukwell, V. G. (1949). J. Brit. Grassl. Soc. 4, 111.CrossRefGoogle Scholar
Raymond, W. F., Kemp, C. D., Kemp, A. W. & Harris, C. E. (1954). J. Brit. Grassl. Soc. 9, 69.CrossRefGoogle Scholar
Raymond, W. F., Minson, D. J. & Harris, C. E. (1956). Int. Grassl. Congr. VII, Palmerston North, N.Z., p. 123.Google Scholar
Reid, J. T., Woolfolk, P. G., Richards, C. R., Kaufmann, R. W., Loosli, J. K., Turk, K. L., Miller, J. I. & Blaser, R. E. (1950). J. Dairy Sci. 33, 60.CrossRefGoogle Scholar
Reid, J. T., Woolfolk, P. G., Hardison, W. A., Martin, C. M., Brundage, A. L. & Kaufmann, R. W. (1952). J. Nutr. 46, 255.CrossRefGoogle Scholar
Wallace, L. R. (1956). Int. Grassl. Congr. VII, Palmerston North, N.Z., p. 134.Google Scholar
Watson, S. J., Procter, J. & Ferguson, W. S. (1932). J. Agric. Sci. 22, 257.CrossRefGoogle Scholar
Woodman, H. E., Evans, R. E. & Eden, A. (1937). J. Agric. Sci. 27, 212.CrossRefGoogle Scholar