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Environmental temperature, energy metabolism and heat regulation in sheep. II. The partition of heat losses in closely clipped sheep

Published online by Cambridge University Press:  27 March 2009

K. L. Blaxter
Affiliation:
The Hannah Dairy Research Institute, Kirkhill, Ayr
N. McC. Graham
Affiliation:
The Hannah Dairy Research Institute, Kirkhill, Ayr
F. W. Wainman
Affiliation:
The Hannah Dairy Research Institute, Kirkhill, Ayr
D. G. Armstrong
Affiliation:
The Hannah Dairy Research Institute, Kirkhill, Ayr

Extract

1. The heat emission of two closely clipped sheep was studied in forty experiments in which three feeding levels were employed and in which environmental temperatures ranged from 8 to 38° C.

2. The sheep shivered at temperatures below 23° C., but the first reaction to cold was a corrugation of the skin referable to contraction of the fascial muscles.

3. As environmental temperature increased voluntary water consumption and urinary volume increased markedly. Only a small degree of cooling resulted from this warming of large quantities of water through a relatively small temperature gradient.

4. The basal loss of heat by vaporization of water was 316 Cal./m.2/24 hr. in one sheep (3) and 307 Cal./ m.2/24 hr. in the other (23). Increased vaporization occurred at environmental temperatures of 31° C. for the experiments at the low-feeding level, 27° C. at the medium level and 26° C. at the high level. The water-vapour loss increased subsequently by 87 Cal./m.2/24 hr./° C. change in environmental temperature in sheep 3 and by 88 Cal./m.2/24 hr./° C. in sheep 23. Respiratory frequencies increased with increasing heat loss by vaporization. Some evidence suggests that when the water-vapour loss was high the excretion of potassium through the skin was increased.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1959

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References

REFERENCES

Beakley, W. R. & Findlay, J. D. (1955 a). J. Agric. Sci. 45, 339.CrossRefGoogle Scholar
Beakley, W. R. & Findlay, J. D. (1955 b). J. Agric. Sci. 45, 373.CrossRefGoogle Scholar
Blaxter, K. L. (1948). J. Agric. Sci. 38, 207.CrossRefGoogle Scholar
Blaxter, K. L., Graham, N. McC. & Wainman, F. W. (1958). J. Agric. Sci. 52, 41.CrossRefGoogle Scholar
Blaxter, K. L. & Rook, J. A. F. (1956). J. Agric. Sci. 48, 210.CrossRefGoogle Scholar
Burton, A. C. (1934). J. Nutr. 7, 481.CrossRefGoogle Scholar
Burton, A. C. & Edholm, O. G. (1955). Man in a Cold Environment. London. Edward Arnold Ltd.Google Scholar
Capstick, J. W. & Wood, T. B. (1922). J. Agric.Sci. 12, 257.CrossRefGoogle Scholar
DuBois, E. F. (1936). Basal Metabolism in Health and Disease. Lea and Febiger: Philadelphia.Google Scholar
Graham, N. McC., Wainman, F. W., Blaxter, K. L. & Armstrong, D. G. (1958). J. Agric. Sci. 52, 25.Google Scholar
Hardy, J. D. & DuBois, E. F. (1938). J. Nutr. 15, 477.CrossRefGoogle Scholar
Hardy, J. D. & Soderstrom, G. F. (1938). J. Nutr. 16, 494.Google Scholar
Hatfield, H. S. & Pugh, L. G. C. (1951). Nature, Lond., 168, 918.CrossRefGoogle Scholar
Herrington, L. P. (1949). The range of physiological responses to climatic heat and cold. In The Physiology of Heat Regulation [Newburgh, L. H., editor]. New York: Saunders and Co.Google Scholar
Irving, L., Peyton, L. J. & Monson, M. (1956). J.Appl. Phys. 9, 421.Google Scholar
Lefevre, J. (1901). J. Phys. (06 issue).Google Scholar
Leitch, I. & Thomson, T. S. (1944). Nutr. Abstr. Rev. 14, 197.Google Scholar
Mitchell, H. H. (1927). Annu. Rep. Univ. Illinois Agric. Exp. Sta. p. 155.Google Scholar
Ryder, M. L. (1955). J. Agric. Sci. 45, 311.CrossRefGoogle Scholar
Schaeer, E. A. (1898). Textbook of Physiology, I, p. 838. London: Hodder and Stoughton.Google Scholar
Scholander, P. F., Walters, V., Hock, R. & Irving, L. (1950). Biol. Bull., Woods Hole, 99, 225.CrossRefGoogle Scholar
Tangl, F. (1912). Biochem. Z. 44, 252.Google Scholar
Thompson, H. J., Worstell, D. M. & Brody, S. (1949). Univer. Mo. Agric. Expt. Stn. Res. Bull. no. 436.Google Scholar
Winslow, C. E. A. & Herrington, L. P. (1949). Temperature and Human Life. Princeton: Princeton University Press.Google Scholar