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Models of heat production and critical temperature for growing pigs

Published online by Cambridge University Press:  02 September 2010

J. M. Bruce
Affiliation:
Scottish Farm Buildings Investigation Unit, Craibstone, Bucksburn, Aberdeen AB2 9TR
J. J. Clark
Affiliation:
Scottish Farm Buildings Investigation Unit, Craibstone, Bucksburn, Aberdeen AB2 9TR
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Abstract

1. A deterministic model for thermoneutral heat production of growing pigs on barley-based diets has been developed and validated. The model variables are live weight (20 to 100 kg) and metabolizable energy intake (not less than maintenance). The root-mean-square error for 62 data is 049 MJ/day (3·2%).

2. A deterministic model for heat production of growing pigs below their critical temperature has been developed and validated. The model variables are: air temperature, air velocity, floor type, live weight (20 to 100 kg), and group size. The root-mean-square error for 78 data is 0·77 MJ/day (5·6%).

3. The two heat production models are combined to give a model for the lower critical temperature for growing pigs.

4. These models may be used to quantify and compare the effects on energy balance of different combinations of nutrition and environment. They should help to clarify the issues when practical decisions in pig production are made and should also help in the design of nutritional and physiological experiments.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1979

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References

REFERENCES

Blaxter, K. L. 1969. The Energy Metabolism of Ruminants. 2nd ed., pp. 157158. Hutchinson, London.Google Scholar
Blaxter, K. L. 1977. Environmental factors and their influence on the nutrition of farm livestock. In Nutrition and the Climatic Environment (ed. Haresign, W., Swan, H. and Lewis, D.), pp. 116. Butterworths, London.Google Scholar
Bruce, J. M. 1977. Conductive heat loss from the recumbent animal. Farm Building R. & D. Studies 8: 915.Google Scholar
Close, W. H. 1971. The influence of environmental temperature and plane of nutrition on heat losses from individual pigs. Anim. Prod. 13: 295302.Google Scholar
Close, W. H. and Mount, L. E. 1976. The influence of plane of nutritionand environmental temperature on heat loss and energy retention in the pig. Proc, Nutr. Soc. 35: 60A61A.Google Scholar
Close, W. H. and Mount, L. E. 1978. The effects of plane of nutrition and environmental temperature on the energy metabolism of the growing pig. 1. Heat loss and critical temperature. Br. J. Nutr. 40: 413421.CrossRefGoogle ScholarPubMed
Close, W. H., Mount, L. E. and Start, I. B. 1971. The influence of environmental temperature and plane of nutrition on heat losses from groups of growing pigs. Anim. Prod. 13: 285294.Google Scholar
Fuller, M. F. and Boyne, A. W. 1972. The effects of environmental temperature on the growth and metabolism of pigs given different amounts of food. 2. Energy metabolism. Br. J. Nutr. 28: 373384.CrossRefGoogle ScholarPubMed
Holmes, C. W. and Close, W. H. 1977. The influence of climatic variables on energy metabolism and associated aspects of productivity in the pig. In Nutrition and the Climatic Environment (ed. Haresign, W., Swan, H. and Lewis, D.), pp. 5173. Butter-worths, London.Google Scholar
Hovell, F. D. DeB., Gordon, J. G. and MacPherson, R. M. 1977. Thin sows. 2. Observations on the energy and nitrogen exchanges of thin and normal sows in environmental temperatures of 20 and 5°C. J. agric. Sci., Camb. 89: 523533.CrossRefGoogle Scholar
Institution of Heating and Ventilating Engineers. 1971. IHVE Guide Book A1970. 4th ed. pp. A36. Institute of Heating and Ventilating Engineers, London.Google Scholar
McAdams, W. H. 1954. Heat Transmission. 3rd ed., p. 260. McGraw-Hill Kogakusha, Tokyo.Google Scholar
Mount, L. E. 1968. The Climatic Physiology of the Pig. pp. 38, 76, 134, 142,186. Edward Arnold, London.Google Scholar
Rogers, G. F. C. and Mayhew, Y. R. 1959. Engineering Thermodynamics, Work and Heat Transfer. p. 542. Longman, London.Google Scholar
Verstegen, M. W. A., Close, W. H., Start, I. B. and Mount, L. E. 1973. The effects of environmental temperature and plane of nutrition on heat loss, energy retention and deposition of protein and fat in groups of growing pigs. Br. J. Nutr. 30: 2135.CrossRefGoogle ScholarPubMed
Verstegen, M. W. A. and Van Der Hel, W. 1974. The effects of temperature and type of floor on metabolic rate and effective critical temperature in groups of growing pigs. Anim. Prod. 18: 111.Google Scholar
Webster, A. J. F. 1974. Physiological effects of cold exposure. In Environmental Physiology (ed. Robertshaw, D.), pp. 3369. Butterworths, London.Google Scholar