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Modelling the effects of thermal environment and dietary composition on pig performance: model testing and evaluation

Published online by Cambridge University Press:  18 August 2016

I.J. Wellock*
Affiliation:
Animal Nutrition and Health Department, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
G.C. Emmans
Affiliation:
Animal Nutrition and Health Department, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
I. Kyriazakis
Affiliation:
Animal Nutrition and Health Department, Scottish Agricultural College, West Mains Road, Edinburgh EH9 3JG, UK
*
Address for correspondence: Animal Nutrition and Health Department, Scottish Agricultural College, Bush Estate, Penicuik EH26 0PH, UK. E-mail: [email protected]
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Abstract

A deterministic, dynamic pig growth model predicting the effect of genotype, and the thermal and nutritional environments on food intake, growth and body composition of growing pigs was tested and evaluated against experimental data from the literature. Four sets of experiments meeting the necessary requirement of feeding the pigs ad libitum and reporting sufficient information on trial conditions were chosen to test the model. The parameters used in the model to describe the kind of pig were protein weight at maturity (Pm) the Gompertz rate parameter (B) and the ratio of mature lipid weight (Lm) to Pm. Values for Pm and B used to apply to the pigs in the four experiments were selected as those which gave the maximum daily gains equal to those reported at thermoneutral temperatures on diets not limiting in protein. The value of Lm was chosen as that which gave a value for food conversion ratio close to that seen in the experiment, again at a thermoneutral temperature and on a non-limiting diet. The model was run for each of the experiments from the given start weight until slaughter weight was reached. All pigs were assumed to have their desired bodily composition at the start of the experimental period, which is determined by their genetic descriptors and weight. From the conditions of the experiments, average daily gain (ADG) average daily food intake (ADFI) food conversion ratio (FCR) final body weight, body composition, average daily gains of each of the chemical body components and heat production (HP) were predicted. Generally as temperature increased or the crude protein content of the food increased, ADFI, ADG and the fatness of the pig decreased, whilst protein content increased. Quantitative differences between the model predictions and the observations, were probably due to the greater sensitivity of the model to temperature. This is likely to reflect the omission of long-term adaptation and acclimatization, or to incorrect estimation of the wetness of the pig’s skin. However, model predictions were generally in good quantitative agreement with the observed data over the wide range of treatments tested. This gives support to the value and accuracy of the model for predicting pig performance when the thermal and nutritional environments are manipulated.

Type
Non-ruminant nutrition, behaviour and production
Copyright
Copyright © British Society of Animal Science 2003

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References

Birkett, S. and Lange, K.de. 2001a. A computational framework for a nutrient flow representation of energy utilization by growing monogastric animals. British Journal of Nutrition 86: 661674.Google Scholar
Birkett, S. and Lange, K.de. 2001b. Calibration of a nutrient flow model of energy utilization by growing pigs. British Journal of Nutrition 86: 675689.Google Scholar
Black, J. L. 1995a. Approaches to modelling. In Modelling growth in the pig (ed. Moughan, P.J., Verstegen, M. W. A. and Visser-Reyneveld, M. I.), EAAP publication no. 78, pp. 1122. Wageningen Pers, The Netherlands.Google Scholar
Black, J. L. 1995b. Testing and evaluation of models. In Modelling growth in the pig (ed. Moughan, P. J., Verstegen, M. W. A. and Visser-Reyneveld, M. I.), EAAP publication no. 78, pp. 2331. Wageningen Pers, The Netherlands.Google Scholar
Black, J. L., Campbell, R. G., Williams, I. H., James, K. J. and Davies, G. T. 1986. Simulation of energy and amino acid utilisation in the pig. Research and Development in Agriculture 3: 121145.Google Scholar
Boisen, S., Hvelplund, T., and Weisbjerg, M. R. 2000. Ideal amino acid profiles as a basis for feed protein evaluation. Livestock Production Science 64: 239251.Google Scholar
Bridges, T. C., Turner, L. W., Stahly, T. S., Usry, J. L. and Loewer, O. J. 1992a. Modelling the physiological growth of swine. I. Model logic and growth concepts. Transactions of the American Society of Agricultural Engineers 35: 10191028.Google Scholar
Bridges, T. C., Turner, L. W., Stahly, T. S., Usry, J. L. and Loewer, O. J. 1992b. Modelling the physiological growth of swine. II. Validation of model logic and growth concepts. Transactions of the American Society of Agricultural Engineers 35: 10291033.Google Scholar
Campbell, R. G. 1977. The response of early weaned pigs to various protein levels in a high energy diet. Animal Production 24: 6975.Google Scholar
Campbell, R. G. and Dunkin, A. C. 1983. The influence of nutrition in early life on growth and development of the pig. 3. Effects of energy intake prior and subsequent to 10 kg on growth and development to 30 kg live weight. Animal Production 36: 435443.Google Scholar
Collin, A., Milgen, J.van and Le Dividich, J. 2001. Modelling the effect of high, constant temperature on food intake in young growing pigs. Animal Science 72: 519527.Google Scholar
Emmans, G. C. and Kyriazakis, I. 1995. A general method for predicting the weight of water in the empty bodies of pigs. Animal Science 61: 103108.Google Scholar
Ferguson, N. S. and Gous, R. M. 1997. The influence of heat production on voluntary food intake in growing pigs given protein-deficient diets. Animal Science 64: 365378.Google Scholar
France, J. and Thornley, J. H. M. 1984. Mathematical models in agriculture. Butterworths, London.Google Scholar
Giles, L. R., Dettmann, E. B. and Lowe, R. F. 1988. Influence of diurnally fluctuating high temperature on growth and energy retention of growing pigs. Animal Production 47: 467474.Google Scholar
Harrison, S. H. 1987. Validation of models: methods, applications and limitations. In Computer assisted management of agricultural production systems, pp. 118. Royal Melbourne Institute of Technology, Melbourne.Google Scholar
Knap, P. W. 1999. Simulation of growth in pigs: evaluation of a model to relate thermoregulation to body protein and lipid content and deposition. Animal Science 68: 655679.Google Scholar
Knap, P. W., Roehe, R., Kolstad, K., Pomar, C. and Luiting, P. 2002. Characterization of pig gentoypes. Journal of Animal Science 80: (suppl. 1) 174 (abstr.).Google Scholar
Kyriazakis, I. 2003. The control and prediction of food intake in sickness and in health. In Perspectives in pig science (ed. Wiseman, J., Varley, M. and Kemp, B.), pp. 381403. Nottingham University Press, UK.Google Scholar
Kyriazakis, I. and Emmans, G. C. 1991. Diet selection in pigs: dietary choices made by growing pigs following a period of underfeeding with protein. Animal Production 52: 337346.Google Scholar
Kyriazakis, I. and Emmans, G. C. 1992. The effects of varying protein and energy intakes on growth and body composition of pigs. 1. The effects of energy intake at constant, high protein intake. British Journal of Nutrition 68: 603613.CrossRefGoogle ScholarPubMed
Kyriazakis, I., Emmans, G. C. and Whittemore, C. T. 1990. Diet selection in pigs: choices made by growing pigs given foods of different protein concentrations. Animal Production 51: 189199.Google Scholar
Kyriazakis, I., Emmans, G. C. and Whittemore, C. T. 1991. The ability of pigs to control their protein intake when fed in three different ways. Physiology and Behavior 50: 11971203.Google Scholar
Mount, L. E., Holmes, C. W., Close, W. H., Morrison, S. R. and Start, I. B. 1971. A note on the consumption of water by the growing pig at several environmental temperatures and levels of feeding. Animal Production 13: 561563.Google Scholar
National Research Council. 1998. Nutrient requirements of swine, 10th edition. National Academy Press, Washington, DC.Google Scholar
Nienaber, J. A., Hahn, G. L., McDonald, T. P. and Korthals, R. L. 1996. Feeding patterns and swine performance in hot environments. Transactions of the American Society of Agricultural Engineers 39: 195202.Google Scholar
Nienaber, J. A., Hahn, G. L. and Yen, J. T. 1987a. Thermal environment effects on growing-finishing swine. 1. Growth, food intake and heat production. Transactions of the American Society of Agricultural Engineers 30: 17721775.Google Scholar
Nienaber, J. A., Hahn, G. L. and Yen, J. T. 1987b. Thermal environment effects on growing-finishing swine. 2. Carcass composition and organ weights. Transactions of the American Society of Agricultural Engineers 30: 17761779.Google Scholar
Pomar, C., Harris, D. L. and Minvielle, F. 1991. Computer simulation model of swine production systems. 1. Modelling the growth of young pigs. Journal of Animal Science 69: 14681488.Google Scholar
Schenck, B. C., Stahly, T. S. and Cromwell, G. L. 1992a. Interactive effects of thermal environment and dietary amino acid and fat levels on rate, efficiency and composition of growth of weaning pigs. Journal of Animal Science 70: 37913802.Google Scholar
Schenck, B. C., Stahly, T. S. and Cromwell, G. L. 1992b. Interactive effects of thermal environment and dietary amino acid and fat levels on rate and efficiency of growth of pigs housed in a conventional nursery. Journal of Animal Science 70: 38033811.Google Scholar
Sugahara, M., Baker, D. H., Harmon, B. G. and Jensen, A. H. 1970. Effect of ambient temperature on performance and carcass development in young swine. Journal of Animal Science 31: 5962.Google Scholar
Wellock, I. J., Emmans, G. C. and Kyriazakis, I. 2003. Modelling the effects of thermal environment and dietary composition on pig performance: model logic and concepts. Animal Science 77: 255266.Google Scholar
Whittemore, C. T. and Fawcett, R. H. 1976. Theoretical aspects of a flexible model to simulate protein and lipid growth in pigs. Animal Production 22: 8796.Google Scholar
Whittemore, E. C., Emmans, G. C. and Kyriazakis, I. 2003a. The relationship between live weight and the intake of bulky foods in pigs. Animal Science 76: 89100.Google Scholar
Whittemore, E. C., Emmans, G. C. and Kyriazakis, I. 2003b. The problem of predicting food intake during the period of adaptation to a new food: a model. British Journal of Nutrition 89: 383398.Google Scholar
Wright, R. D. 1979. Validating dynamic models: an evaluation of tests of predictive power. Proceedings of the summer computer simulation conference, pp. 12861296. Simulation Councils Inc., La Jolla, CA.Google Scholar