Hostname: page-component-77c89778f8-gq7q9 Total loading time: 0 Render date: 2024-07-16T13:39:26.345Z Has data issue: false hasContentIssue false
  • English
  • Français

The heat of combustion of the urine of sheep and cattle in relation to its chemical composition and to diet

Published online by Cambridge University Press:  09 March 2007

K. L. Blaxter ,
J. L. Clapperton  and
A. K. Martin
K. L. Blaxter
Affiliation:
Hannah Dairy Research Institute, Ayr
J. L. Clapperton
Affiliation:
Hannah Dairy Research Institute, Ayr
A. K. Martin
Affiliation:
Hannah Dairy Research Institute, Ayr
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. The results of over 500 determinations of the heat of combustion of the urine produced by cattle and sheep have been analysed statistically. 2. The analytical errors for nitrogen, carbon and heat of combustion were ±0.54, ±1.4 and ±2.2%. The error attached to an estimate of the heat of combustion of the urine produced by an individual sheep in 4 days was ± 10%.3. At the maintenance level of feeding, the heat of combustion of the urine (U kcal/ 100 kcal food) was related to the crude protein content of the diet (P%)by the equation

U = 0.25P+1.6

with a residual standard deviation of ±0.88 kcal/100 kcal.4. Regression analysis of the relation between the heat of combustion of urine and its N content showed significant differences with diet. The heat of combustion of the urine of sheep was 9.7 kcal/g C and of cattle 10.3 kcal/g C, and did not vary with diet. 5. It is shown that the variation in the heat of combustion of urine/g N and its relative constancy/g C arises largely from variation, from diet to diet, in the proportion of the N excreted as hippurate. 6. The results have been combined with the results of a similar analysis (Blaxter & Clapperton, 1965) of methane production by sheep to show that the ratio of metabolizable energy to digested energy varies very little from mean values of 0.82 for roughages, 0.85 for cereals and 0.79 for oilseed cakes and meals.

Type
Research Article
Information
British Journal of Nutrition , Volume 20 , Issue 3 , September 1966 , pp. 449 - 460
Copyright
Copyright © The Nutrition Society 1966

References

REFERENCES

Armsby, H. P. (1908). Principles of Animal Nutrition. New York: John Wiley and Sons.Google Scholar
Blaxter, K. L. & Clapperton, J. L. (1965). Br. J. Nutr. 19, 511.Google Scholar
Elliott, J. M. & Loosli, J. K. (1959). J. Dairy Sci. 42, 836.CrossRefGoogle Scholar
Graham, N. McC., Blaxter, K. L. & Armstrong, D. G. (1958). E.A.A.P. Publs Eur. Ass. Anim. Prod. no. 8, p. 157.Google Scholar
Nehring, K., Hoffmann, L., Schiemann, R. & Jentsch, W. (1963). Arch. Tierernähr. 13, 193.CrossRefGoogle Scholar
Paladines, O. L., Reid, J. T., Van Niekerk, B. D. H. & Bensadoun, A. (1964). J. Anim. Sci. 23, 528.CrossRefGoogle Scholar
Street, J. C., Butcher, J. E. & Harris, L. E. (1964). J. Anim. Sci. 23, 1039.CrossRefGoogle Scholar
Wainman, F. W. & Paterson, D. (1963). J. agric. Sci., Camb. 61, 253.CrossRefGoogle Scholar