Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-23T20:52:21.707Z Has data issue: false hasContentIssue false
  • English
  • Français

Some errors in the determination of nitrogen retention of sheep by nitrogen balance studies

Published online by Cambridge University Press:  09 March 2007

A. K. Martin
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. Loss of NH3 N from faeces and urine between voiding and collection and also losses in expired air, eructed gas and from the skin of wether sheep 2–3 years old given a ration of 400, 700, 1000 or 1300 g dried grass/day have been measured. 2. Losses of NH3 from faeces were negligible, and the loss from urine depended on the temperature and pH at which it was collected. Collection at neutral pH resulted in losses of up to 9.7% of the urinary N as NH3 gas if an acid trap were not incorporated in the collection apparatus. The average loss of N on collection of urine at pH values below 2.0 was 1.33% when the ambient temperature was between 25 and 28°, and 0.97% when it was between 15 and 18°. 3. Very little NH3 was lost in expired air or eructed gas, but when total NH3 loss other than that from urine was determined, an average loss of 3.14±0.55 mg N/kg body-weight per day was found. This loss was independent of food intake and larger than the loss of N in suint which was estimated to range from 0.59 to 2.55 mg N/kg body-weight per day with the rations given. It was concluded that the larger losses found in some experiments were due to splashing of urine on to the fleece during collection and subsequent loss of this urine N as NH3. It was shown that the losses of NH3 N due to errors in urine collection and failure to consider dermal losses ranged between 1.2 and 2.6% of the total determined losses in faeces and urine for sheep fed on a variety of diets and that the losses varied inversely with intake of N.

Type
Research Article
Information
British Journal of Nutrition , Volume 20 , Issue 2 , May 1966 , pp. 325 - 337
Copyright
Copyright © The Nutrition Society 1966

References

REFERENCES

Allison, J. B. & Bird, J. W. C. (1964). In Mammalian protein Metabolism. Vol. 1, p. 483. [Munro, H. N. and Allison, J. B., editors.] New York and London: Academic Press Inc.CrossRefGoogle Scholar
Bock, H. D., Nehring, K., Schiemann, R., Hovorka, F., Horszczaruk, F. & Angelowa, L. (1964). Arch. Tierernähr. 14, 13.CrossRefGoogle Scholar
Butterworth, M. H. (1963). J. Sci. Fd Agric. 13, 6.CrossRefGoogle Scholar
Crowther, A. B. & Large, R. S. (1956). Analyst, Lond., 81, 64.Google Scholar
Daly, R. A. & Carter, H. B. (1955). Aust. J. agric. Res. 6, 476.CrossRefGoogle Scholar
Harris, L. E. & Mitchell, H. H. (1941). J. Nutr. 22, 167.CrossRefGoogle Scholar
Henry, K. M. (1965). Br. J. Nutr. 19, 25.Google Scholar
Jacquez, J. A., Poppell, J. W. & Jeltsch, R. (1959). Science, N. Y., 129, 269.CrossRefGoogle Scholar
Nehring, K. (1957). Biochem. Z. 328, 549.Google Scholar
Tetlow, J. A. & Wilson, A. L. (1964). Analyst, Lond., 89, 453.CrossRefGoogle Scholar
Van Slyke, D. D. & Cullen, G. E. (1914). J. biol. Chem. 19, 211.Google Scholar
Wainman, F. W. & Blaxter, K. L. (1958). Publs Eur. Ass. Anim. Prod. no. 8, p. 80.Google Scholar
Wainman, F. W. & Paterson, D. (1963). J. agric. Sci., Camb., 61, 253.CrossRefGoogle Scholar