Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-19T07:30:25.306Z Has data issue: false hasContentIssue false

The fasting metabolism of Brahman, Africander and Hereford×Shorthorn cattle

Published online by Cambridge University Press:  09 March 2007

J. E. Vercoe
Affiliation:
CSIRO Division of Animal Genetics, Cattle Research Laboratory, Rockhampton, Qld 4700, Australia
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 fasting metabolism of twenty-seven animals, nine Brahmans, nine Africanders and nine Hereford × Shorthorns was measured after fasts of 96 h duration. Urine was collected over successive 24 h intervals and gas exchange was determined 96–103 h after the last meal.

2. Urinary urea decreased and creatinine increased throughout the fasting period. There was no difference between breeds in the urinary excretion of nitrogen, urea and creatinine on the 4th day of fasting (72–96 h). Excretion of nitrogen, urea and creatinine increased by 259, 197 and 45 mg/kg increase in fasted weight and by 8.9, 7.6 and 0.91 mg/kcal increase in fasting metabolism respectively. Protein oxidation accounted for 25.6, 21.7 and 22.7% of the fasting heat production of Brahman, Africander and Hereford × Shorthorn cattle respectively, values which were not significantly different.

3. The breeds differed in fasting metabolism per kg fasted weight ( P < 0.05) and in fasting metabolism adjusted for fasted weight (0.05 < P < 0.10), mainly owing to lower values for the Brahmans. The respective values for the Brahmans, Africanders and Hereford × Short-horns were 20.7, 25.2 and 24.1 kcal/kg (86.6, 105.4 and 100.8 kJ/kg) and 5.856, 6.947 and 6.600 Mca1/24 h (24.50, 29.07 and 27.61 MJ/24 h) at a fasted weight of 277 kg. The variation in fasting metabolism between animals within breeds, expressed as a coefficient of variation, was 13.7%.

4. The results are discussed in relation to published estimates of fasting metabolism, possible reasons for the breed difference and the relation of fasting metabolism to heat tolerance.

Type
Research Article
Copyright
Copyright © The Nutrition Society 1970

References

REFERENCES

Blaxter, K. L. (1962). Energy Metabolism of Ruminants. London: Hutchinson.Google Scholar
Blaxter, K. L. & Wainman, F. W. (1966). Br. J. Nutr. 20, 103.Google Scholar
Brockway, J. M. (1965). Publs Eur. Ass. Anim. Prod. no. 11, p. 395.Google Scholar
Brouwer, E. (1965). Publs Eur. Ass. Anim. Prod. no. 11, p. 442.Google Scholar
Findlay, J. D. (1950). Bull. Hannah Dairy Res. Inst. no. 9.Google Scholar
Flatt, W. P. & Coppock, C. E. (1963). J. Dairy Sci. 46, 638.Google Scholar
Flatt, W. P. & Coppock, C. E. (1965). In Physiology of Digestion in the Ruminant, p. 240 [Dougherty, R. W., editor]. Washington: Butterworth.Google Scholar
Frisch, J. E. & Vercoe, J. E. (1969). Aust. J. agric. Res. 20, 1189.Google Scholar
Graham, N. McC. (1967). Aust. J. ugric. Res. 18, 127.Google Scholar
Graham, N. McC. (1968). Aust. J. agric. Res. 19, 821.Google Scholar
Johnston, J. E., Hamblin, F. B. & Schrader, G. T. (1958). J. Anim. Sci. 17, 473.Google Scholar
Kennedy, J. F. & Turner, H. G. (1959). Rep. Div. Anim. Hlth Prod. C.S.I.R.O. Aust. no. 8 (series SW-3).Google Scholar
Kibler, H. H. & Brody, S. (1950). Res. Bull. Mo. agric. Exp. Stn no. 464.Google Scholar
Kibler, H. H. & Brody, S. (1951). Res. Bull. Mo. agric. Exp. Stn no. 473.Google Scholar
Kibler, H. H. & Brody, S. (1954). Res. Bull. Mo. agric. Exp. Stn no. 574.Google Scholar
Kleiber, M. (1945). Nutr. Abstr. Rev. 15, 207.Google Scholar
Marston, H. R. (1948). Aust. J. sci. Res. B 1, 93.Google Scholar
Rhoad, A. O. (1940). Emp. J. exp. Agric. 8, 190.Google Scholar
Schleger, A. V. & Turner, H. G. (1965). Aust. J. agric. Res. 16, 92.Google Scholar
Snedecor, G. W. & Cochran, W. G. (1967). Statistical Methods 6th ed. Ames, Iowa: Iowa State University Press.Google Scholar
Turner, H. G. & Thornton, R. F. (1966). Proc. Aust. Soc. Anim. Prod. 6, 413.Google Scholar
Vercoe, J. E. (1967). Aust. J. agric. Res. 18, 1003.Google Scholar
Vercoe, J. E. (1969). Aust. J. agric. Res. 20, 607.CrossRefGoogle Scholar
Worstell, D. M. & Brody, S. (1953). Res. Bull. Mo. agric. Exp. Stn no. 515.Google Scholar