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Acclimatisation of Scottish Blackface sheep to cold. 1. Rectal temperature responses

Published online by Cambridge University Press:  02 September 2010

J. Slee
Affiliation:
A.R.C. Animal Breeding Research Organisation, Edinburgh, 9
A. R. Sykes
Affiliation:
A.R.C. Animal Breeding Research Organisation, Edinburgh, 9
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Extract

Closely shorn Scottish Blackface female sheep aged 9–14 months, half on high plane and half on low plane nutrition, were subjected, in climate chambers, to two short acute cold exposures down to – 20° C. The exposures were separated by a period of two weeks in either a thermoneutral environment ( + 30° C.) or a subcritical environment ( + 8° C.). Thirty-seven out of 40 sheep showed a greater resistance to body cooling at the second exposure. The mean rates of fall of rectal temperature (in° C. per 100 min. exposure) were 0·42 at the first exposure and 0·22 at the second exposure. One group of sheep showed virtually complete resistance to cooling at second exposure under the specific test conditions used. The highly significant increase in cooling resistance was taken as a measure of acclimatisation.

The main conclusions were as follows:

1. Blackface sheep could acclimatise to cold as a result of one acute exposure to cold lasting about 8 hours.

2. Acclimatisation was slightly greater amongst sheep kept at a subcritical temperature (+8° C.) between acute exposures.

3. Additional data suggested that some acclimatisation resulted from 2 weeks prior exposure to +8° C. alone; but none was induced by 2 weeks prior habituation to the climate chamber environment at + 30° C.

4. Sheep on high plane nutrition showed greater initial cold resistance and slightly greater ability to acclimatise than those on low plane nutrition.

5. Cold resistance was more closely related to recent weight gain than to absolute body weight.

6. There was great individual variation in initial cold resistance and in ability to acclimatise.

7. Sheep kept at + 8° C. between acute cold exposures maintained significantly lower rectal temperatures than those kept at +30° C.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1967

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References

REFERENCES

Adolph, E. F., & Molnar, G. W., 1946. Exchanges of heat and tolerances to cold in men exposed to outdoor weather. Amer. J. Physiol., 146: 507537.CrossRefGoogle ScholarPubMed
Adolph, E. F., & Richmond, J., 1956. Adaptation to cold in the golden hamster and ground squirrel, measured chiefly by rates of body cooling. J. Appl. Physiol., 9: 5358.CrossRefGoogle ScholarPubMed
Alexander, G., 1961. Temperature regulation in the newborn lamb. III. Effect of environmental temperature on metabolic rate, body temperatures and respiratory quotient. Aust. J. agric. Res., 12: 11521174.CrossRefGoogle Scholar
Armstrong, D. G., Blaxter, K. L., Clapperton, J. L., Graham, N. McC., & Wainman, F. W., 1960. Heat production and heat emission of two breeds of sheep. J. agric. Sci., 55: 395401.CrossRefGoogle Scholar
Blair, J. R., 1951. Cold Injury. Trans. 1st Conf. Josiah Macy Jnr. Foundation, New York.Google Scholar
Blaxter, K. L., Graham, N. McC., & Wainman, F. W., 1959. Environmental temperature, energy metabolism and heat regulation in sheep. III. The metabolism and thermal exchanges of sheep with fleeces. J. agric. Sci., 52: 4149.CrossRefGoogle Scholar
Bligh, J., Ingram, D. L., Keynes, R. D., & Robinson, S. G., 1965. The deep body temperature of an unrestrained Welsh Mountain sheep recorded by a radiotelemetric technique during a 12-month period. J. Physiol., 176: 136144.CrossRefGoogle ScholarPubMed
Budd, G. M., 1962. Acclimatization to cold in Antarctica as shown by rectal temperature response to a standard cold stress. Nature, 193: 886.CrossRefGoogle ScholarPubMed
Budd, G. M., 1964. General acclimatization to cold in men studied before, during and after a year in Antarctica. Australian National Antarctic Research Expeditions Reports. B IV: 184.Google Scholar
Budd, G. M., & Warhaft, N., 1966. Body temperature, shivering, blood pressure and heart rate during a standard cold stress in Australia and Antarctica. J. Physiol., 186: 216232.CrossRefGoogle ScholarPubMed
Cottle, W., & Carlson, L. D., 1954. Adaptive changes in rats exposed to cold: caloric exchange. Amer. J. Physiol., 178: 305308.Google Scholar
Davis, T. R. A., 1961. Chamber cold acclimatization in man. J. Appl. Physiol., 16: 10111015.CrossRefGoogle ScholarPubMed
Davis, T. R. A., 1963. Acclimatization to cold in man. In Temperature, its Measurement and Control in Science and Industry. III. Biology and Medicine. Reinhold, New York.Google Scholar
Depocas, F., Hart, J. S., & Heroux, O., 1957. Energy metabolism of the white rat after acclimation to warm and cold environments. J. Appl. Physiol., 10: 393397.CrossRefGoogle ScholarPubMed
Gelineo, M. S., 1934. Influence du milieu thermique d'adaptation sur la thermogenese des homeothermes. Ann. physiol, phisicochim. Biol., 10: 10831115.Google Scholar
Glaser, E. M., 1950. Acclimatization to heat and cold. J. Physiol., 110: 330337.CrossRefGoogle Scholar
Glaser, E. M., & Shephard, R. J., 1963. Simultaneous experimental acclimatization to heat and cold in man. J. Physiol., 169: 592602.CrossRefGoogle ScholarPubMed
Hart, J. S., 1953. Energy metabolism of the white footed mouse, Peromyscus leucopus noveboracensis, after acclimatization at various environmental temperatures. Canad. J. Zool., 31: 99105.CrossRefGoogle Scholar
Hart, J. S., 1957. Climatic and temperature induced changes in the energetics of homeotherms. Rev. Canad. Biol., 16: 133174.Google ScholarPubMed
Hart, J. S., 1963. Physiological responses to cold in non-hibernating homeotherms. In Temperature, its Measurement and Control in Science and Industry. III. Biology and Medicine. Reinhold, New York.Google Scholar
Heroux, O., Hart, J. S., & Depocas, F., 1956. Metabolism and muscle activity ot anesthetized warm and cold acclimated rats on exposure to cold. J. Appl. Physiol., 9: 399403.Google Scholar
Horvath, S. M., Freedman, A., & Golden, H., 1947. Acclimatization to extreme cold. Amer. J. Physiol., 150: 99108.CrossRefGoogle ScholarPubMed
Joyce, J. P., & Blaxter, K. L., 1964. Effect of air movement, air temperature and infrared radiation on the energy requirements of sheep. Brit. J. Nutr., 18: 527.Google Scholar
Leblanc, J., 1956. Evidence and meaning of acclimatization to cold in man. J. Appl. Physiol, 9: 595598.Google Scholar
Pohl, H., & Hart, J. S., 1965. Thermoregulation and cold acclimation in a hibernator, citellus tridecemlineatus. J. Appl. Physiol., 20: 398404.Google Scholar
Purser, A. F., 1967. Proc. 9th Int. Congr. Anim. Prod. Edinb. (in press).CrossRefGoogle Scholar
Purser, A. F., & Pilkington, J. M., 1958. Fibre medullation in Blackface ewes and hoggs. J. agric. Sci., 51: 257264.Google Scholar
Sellers, E. A., Reichman, S., & Thomas, N., 1951. Acclimatization to cold: natural and artificial. Amer. J. Physiol., 167: 644650.CrossRefGoogle ScholarPubMed
Slee, J., 1966. Variation in the responses of shorn sheep to cold exposure. Anim. Prod., 8: 425434.Google Scholar