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Measuring hunger in the pig using operant conditioning: The effect of food restriction

Published online by Cambridge University Press:  02 September 2010

A. B. Lawrence ,
M. C. Appleby  and
H. A. Macleod
A. B. Lawrence
Affiliation:
Edinburgh School of Agriculture, West Mains Road, Edinburgh EH9 3JG
M. C. Appleby
Affiliation:
Edinburgh School of Agriculture, West Mains Road, Edinburgh EH9 3JG
H. A. Macleod
Affiliation:
Department of Psychology, University of Edinburgh, George Square, Edinburgh EH8 9JZ
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Abstract

Operant conditioning techniques were used to measure the feeding motivation (hunger) of pigs restricted to the low food levels used under certain commercial conditions. Six Large White × Landrace boars were maintained in individual pens where they received their daily food allowance. Initially food was available ad libitum; subsequently boars were restricted proportionately to 0·8, 0·6 and 0·4 of their ad libitum intake in a Latin-square design. Finally boars were again offered their previously measured ad libitum intake (treatment 1·0). Hunger was measured by conditioning boars to press a panel 10 times to receive a 7-g reward of food. Operant response rates were measured over 20-min sessions during each of the treatments and at three times of day (pre-feeding, immediately post feeding and 5 h post feeding).

Operant response rate was strongly affected by restricting food allowance (means: treatment 1·0, 42 panel presses; 0·8, 212; 0·6, 266; 0·4, 320). There was a signficant interaction between food allowance and time of day (P < 0·001). Treatments did not vary in response rate before feeding. Treatments 1·0 and 0·8 depressed response rate post feeding (P < 0·001) and treatment 1·0 also 5 h post feeding (P < 0·001). Response rates on treatments 0·6 and 0·4 did not vary significantly from one another or with time of day.

Restricting pigs to low food levels resulted in a high level of hunger throughout the day. This was so even for food allowances that met current recommended feeding levels sufficient for maintenance and low weight gain (treatment 0·6 equivalent to 1·3 times maintenance). Commercial levels of feeding for the pig breeding population whilst meeting production needs do not satisfy feeding motivation. The hunger resulting from low food levels may act as a major source of stress under certain husbandry conditions such as tether and stall systems for dry sows, where sows are subject to both physical and food restriction.

Type
Research Article
Information
Animal Production , Volume 47 , Issue 1 , August 1988 , pp. 131 - 137
Copyright
Copyright © British Society of Animal Science 1988

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References

Agricultural Research Council. 1981. The Nutrient Requirements of Pigs. Commonwealth Agricultural Bureaux, Slough.Google Scholar
Appleby, M. C. and Lawrence, A. B. 1987. Food restriction as a cause of stereotypic behaviour in tethered gilts. Animal Production 45: 103–110.Google Scholar
Close, W. H. 1987. Some conclusions of the AFRC working party on the energy requirements of sows and boars. Animal Production 44: 464 (Abstr.).Google Scholar
Cole, D. J. A. 1982. Nutrition and reproduction. In Control of Pig Reproduction (ed. Cole, D. J. A. and Foxcroft, G. R.), pp. 603–619. Butterworths, London.CrossRefGoogle Scholar
Cronin, G. M., Tartwuk, J. M. F. M. Van, Hel, W. Van Der and Verstegen, M. W. A. 1986. The influence of degree of adaptation to tether-housing by sows in relation to behaviour and energy metabolism. Animal Production 42: 257–268.Google Scholar
Herrnstein, R. J. 1961. Stereotypy and intermittent reinforcement. Science 133: 2067–2069.CrossRefGoogle ScholarPubMed
Hodos, W. 1961. Progressive ratio as a measure of reward strength. Science 134: 943–944.CrossRefGoogle ScholarPubMed
Houston, A. and Sumida, B. 1985. A positive feedback model for switching between two activities. Animal Behaviour 33: 315–325.CrossRefGoogle Scholar
Hsia, L. C. and Wood-Gush, D. G. M. 1983. The temporal patterns of food intake and allelomimetic feeding by pigs of different ages. Applied Animal Ethology 11: 271–282.CrossRefGoogle Scholar
Le Magnen, J. 1985. Hunger. Cambridge University Press, Cambridge.Google Scholar
Marwine, A. G. and Collier, G. 1971. Instrumental and consummatory behaviour as a function of rate of weight loss and weight maintenance schedule. Journal of Comparative and Physiological Psychology 74: 441–447.CrossRefGoogle Scholar
Miller, N. E. 1955. Shortcomings of food consumption as a measure of hunger: results from other behavioural techniques. Annals of the New York Academy of Sciences 63: 141–143.CrossRefGoogle Scholar
Rushen, J. P. 1985. Stereotypies, aggression and the feeding schedules of tethered sows. Applied Animal Behaviour Science 14: 137–147.CrossRefGoogle Scholar
Teitelbaum, P. 1966. The use of operant methods in the assessment and control of motivational states. In Operant Behaviour. Areas of Research and Application (ed. Honig, W. K.), pp. 565–608. Appleton-Century-Crofts, New York.Google Scholar
Webster, A. J. F. 1985. Farm animal welfare: the needs of animals and the wishes of society. Animal Production 40: 530 (Abstr.).Google Scholar
Whittemore, C. T., Fraser, D. and Darroch, R. L. 1977. Aspects of ingestive behaviour which may influence the productivity of piglets and sows. British Veterinary Journal 133: 100 (Abstr.).Google Scholar