Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-23T07:14:09.862Z Has data issue: false hasContentIssue false

Further studies on the heat production and effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management

Published online by Cambridge University Press:  02 September 2010

K. J. McCracken
Affiliation:
Agricultural and Food Chemistry Research Division, Department of Agriculture for Northern Ireland, Newforge Lane, Belfast BT9 5PX
R. Gray
Affiliation:
Agricultural and Food Chemistry Research Division, Department of Agriculture for Northern Ireland, Newforge Lane, Belfast BT9 5PX
Get access

Abstract

In two separate experiments pigs were weaned at 14 or 28 days and heat production was determined in an open-circuit respiration chamber at temperatures above and below the lower critical temperature (Tcl) at intervals during the post-weaning period.

With 14-day weaned pigs the mean 24 h heat production above Tc1 averaged 267, 328, 474 and 554 kJ/h per m2 at 3, 9, 15 and 21 days post weaning respectively. The mean thermal conductance (H/AT, kJ/h per m2 per °ΔT, where H is total heat production, m2 is the surface area calculated as 0·097 M kg0·633 and °Δ is the difference between rectal temperature, taken at 39°, and air temperature) below TC1 was calculated as 20·5, 20·1, 23·1 and 24·2 at 17, 23, 29 and 35 days of age respectively and the corresponding values for Tc1 were 25·9, 23·0, 18·4 and 16·0°C.

With 28-day weaned pigs the mean 24 h heat production above Tc1 averaged 280, 361 and 445 kJ/h per m2 at 3, 9 and 15 days post weaning. The calculated values for H/ΔT were 19·7, 20·8 and 21·6 and the corresponding values of Tcl were 24·8, 21·7, and 18·8°C at 31, 37 and 43 days of age respectively.

The results are discussed in relation to previous studies on 10-day and 28-day weaned pigs and in relation to the practical implications for pigs weaned into controlled-environment accommodation.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1984

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Ball, R. O. and Aherne, F. X. 1982. Effect of diet complexity and feed restriction on the incidence and severity of diarrhoea in early-weaned pigs. Can. J. Anim. Sci. 62: 907913.CrossRefGoogle Scholar
Brody, S. 1945. Bioenergetics and Growth. Reinhold, New York.Google Scholar
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. Butterworth, London.Google Scholar
Le Dividich, J., Vermorel, M., Noblet, J., Bouvier, J. C. and Aumaitre, A. 1980. Effects of environmental temperature on heat production, energy retention, protein and fat gain in early weaned piglets. Br. J. Nutr. 44: 313323.CrossRefGoogle ScholarPubMed
McCracken, K. J. and Caldwell, B. J. 1980. Studies of diurnal variations of heat production and the effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management. Br. J. Nutr. 43: 321328.CrossRefGoogle ScholarPubMed
McCracken, K. J., Caldwell, B. J. and Walker, N. 1979. A note on the effect of temperature on the performance of early-weaned pigs. Anim. Prod. 29: 423426.Google Scholar
Shields, R. G. Jr, Ekstrom, K. E. and Mahan, D. C. 1980. Effect of weaning age and feeding method on digestive enzyme development in swine from birth to ten weeks. J. Anim. Sci. 50: 257265.CrossRefGoogle ScholarPubMed
Wahlstrom, R. C., Hauser, L. A. and Libal, G. W. 1974. Effects of low lactose whey, skim milk and sugar on diet palatability and performance of early-weaned pigs. J. Anim. Sci. 38: 12671271.CrossRefGoogle Scholar