Hostname: page-component-78c5997874-v9fdk Total loading time: 0 Render date: 2024-11-13T04:00:32.142Z Has data issue: false hasContentIssue false
  • English
  • Français

Development of a dynamic, mechanistic model of lamb metabolism and growth

Published online by Cambridge University Press:  02 September 2010

R. D. Sainz  and
J. E. Wolff
R. D. Sainz
Affiliation:
Growth Physiology Group, Ruakura Agriculture Centre, Ministry of Agriculture and Fisheries, Hamilton, New Zealand
J. E. Wolff
Affiliation:
Growth Physiology Group, Ruakura Agriculture Centre, Ministry of Agriculture and Fisheries, Hamilton, New Zealand
Get access

Abstract

A dynamic, mechanistic model of lamb metabolism and growth was developed for the purpose of evaluating hypotheses regarding the mechanisms of action of growth promotants. The model relates tissue growth to DNA accretion and protein turn-over. State variables include circulating amino acids, glucose, lipids and acetate; four protein pools (carcass, viscera, other tissues and wool) and storage triacylglycerol are also included. Equations are mainly of the Michaelis-Menten form, allowing for nutrient utilization patterns to be determined by relative tissue affinities for substrates (ko.5), enzymatic capacities (Vmax) and substrate concentrations ([S]). Protein degradation rates are defined as first-order with respect to protein. The model adequately simulated growth from 20 to 40 kg empty body weight. Simulated changes in nutrient input yielded reasonable energy balance response patterns, although theoretical growth efficiencies were greater than those observed in practice. Variations in volatile fatty acid absorption patterns were accommodated well, with predicted nitrogen retention closely approximating experimental observations. The model also responded appropriately to changes in dietary protein level, with body fat varying inversely with amino acid absorption. In summary, the model was found to perform adequately for the purpose of examining mechanisms responsible for alteration of growth and body composition.

Keywords

growthlambsmathematical modelsmetabolism
Type
Research Article
Information
Animal Production , Volume 51 , Issue 3 , December 1990 , pp. 535 - 549
Copyright
Copyright © British Society of Animal Science 1990

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

Acsl. 1986. Advanced Continuous Simulation Language Reference Manual. Mitchell and Gauthier Associates, Concord, Massachussetts.Google Scholar
Agricultural Research Council. 1980. The Nutrient Requirements of Ruminant Livestock. Commonwealth Agricultural Bureaux, Farnham Royal.Google Scholar
Annison, E. F., Brown, R. E., Leng, R. A., Lindsay, D. B. and West, C. E. 1967. Rates of entry and oxidation of acetate, glucose, D(-)–3-hydroxybutyrate, palmitate, oleate and stearate, and rates of production and oxidation of propionate and butyrate in fed and starved sheep. Biochemical Journal 104: 135–147.Google Scholar
Annison, E. F., Lindsay, D. B. and White, R. R. 1963. Metabolic interrelations of glucose and lactate in sheep. Biochemical Journal 88: 243–248.CrossRefGoogle ScholarPubMed
Annison, E. F. and White, R. R. 1961. Glucose utilization in sheep. Biochemical Journal 80: 162–169.CrossRefGoogle ScholarPubMed
Baldwin, R. L. and Black, J. L. 1979. Simulation of the effects of nutritional and physiological status on the growth of mammalian tissues: description and evaluation of a computer program. Animal Research Laboratory Technical Paper No. 6. Commonwealth Scientific and Industrial Research Organization, Melbourne.Google Scholar
Baldwin, R. L., France, J. and Gill, M. 1987. Metabolism of the lactating cow. I. Animal elements of a mechanistic model. Journal of Dairy Research 54: 77–105.CrossRefGoogle ScholarPubMed
Baldwin, R. L., Smith, N. E., Taylor, J. B. and Sharp, M. 1980. Manipulating metabolic parameters to improve growth rate and milk secretion. Journal of Animal Science 51: 1416–1428.CrossRefGoogle ScholarPubMed
Ballard, F. J., Hanson, R. W. and Kronfeld, D. S. 1969. Gluconeogenesis and lipogenesis in tissue from ruminant and nonruminant animals. Proceedings of the Federation of American Societies for Experimental Biology 28: 218–231.Google ScholarPubMed
Berg, R. T. and Butterfield, R. M. 1976. New Concepts of Cattle Growth. Wiley, New York.Google Scholar
Bergman, E. N. 1968. Glycerol turnover in the nonpregnant and ketotic pregnant sheep. American Journal of Physiology 215: 865–873.CrossRefGoogle ScholarPubMed
Bergman, E. N. 1975. Production and utilization of metabolites by the alimentary tract as measured in portal and hepatic blood. In Digestion and Metabolism in the Ruminant (ed. McDonald, I. W. and Warner, A. C. I.), Proceedings of the IV International Symposium on Ruminant Physiology, pp. 292–305. University of New England Publishing Unit, Armidale, NSW Australia.Google Scholar
Black, J. L., Gill, M., Beever, D. E., Thornley, J. H. M. and Oldham, J. D. 1987a. Simulation of the metabolism of absorbed energy-yielding nutrients in young sheep: efficiency of utilization of acetate. Journal of Nutrition 117: 105–115.CrossRefGoogle Scholar
Black, J. L., Gill, M., Thornley, J. H. M., Beever, D. E. and Oldham, J. D. 1987b. Simulation of the metabolism of absorbed energy-yielding nutrients in young sheep: efficiency of utilization of lipid and amino acid. Journal of Nutrition 117: 116–128.CrossRefGoogle Scholar
Boorman, K. N. 1980. Dietary constraints on nitrogen retention. In Protein Deposition in Animals (ed. Buttery, P. J. and Lindsay, D. B.), pp. 147–166. Butterworths, London.Google Scholar
Brody, S. 1945. Bioenergetics and Growth: with Special Reference to the Efficiency Complex in Domestic Animals. Reinhold, New York.Google Scholar
Bryant, D. T. W. and Smith, R. W. 1982. Protein synthesis in muscle of mature sheep. Journal of Agricultural Science, Cambridge 98: 639–643.CrossRefGoogle Scholar
Buttery, P. J., Beckerton, A., Mitchell, R. M., Davies, K. and Annison, E. F. 1975. The turnover rate of muscle and liver protein in sheep. Proceedings of the Nutrition Society 34: 91A–92A (Abstr.).Google ScholarPubMed
Cheek, D. B., Holt, A. B., Hill, D. E. and Talbert, J. L. 1971. Skeletal muscle cell mass and growth: the concept of the deoxyribonucleic acid unit. Pediatric Research 5: 312–328.Google Scholar
Crist, K. 1983. Simulation of animal growth: A combined model with short and long term dynamics. PhD Dissertation, University of California, Davis.Google Scholar
Davis, S. R., Barry, T. N. and Hughson, G. A. 1981. Protein synthesis in tissues of growing lambs. British Journal of Nutrition 46: 409–419.CrossRefGoogle ScholarPubMed
Dent, J. B. and Blackie, M. J. 1979. Systems Simulation in Agriculture. Applied Science Publishers, London.CrossRefGoogle Scholar
France, J. and Thornley, J. H. M. 1984. Mathematical Models in Agriculture. A Quantitative Approach to Problems in Agriculture and Related Sciences. Butterworths, London.Google Scholar
Freedland, R. A. and Briggs, S. 1977. A Biochemical Approach to Nutrition. Chapman and Hall, New York.CrossRefGoogle Scholar
Gill, M., Thornley, J. H. M., Black, J. L., Oldham, J. D. and Beever, D. E. 1984. Simulation of the metabolism of absorbed energy-yielding nutrients in young sheep. British Journal of Nutrition 52: 621–649.Google Scholar
Hammond, J. 1932. Growth and the Development of Mutton Qualities in the Sheep. Oliver and Boyd, London.Google Scholar
Hecker, J. F. 1983. The Sheep as an Experimental Animal. Academic Press, New York.Google Scholar
Hopkins, D. L. and Tulloh, N. M. 1985. Effects of a severe nutritional check in early post-natal life on the subsequent growth of sheep to the age of 12-14 months. Changes in body weight, wool and skeletal growth and effects at the cellular level. Journal of Agricultural Science, Cambridge 105: 551–562.CrossRefGoogle Scholar
Huxley, J. S. 1932. Problems of Relative Growth. Methuen, London.Google Scholar
Ingle, D. L., Bauman, D. E., Mellenberger, R. W. and Johnson, D. E. 1973. Lipogenesis in the ruminant: effect of fasting and refeeding on fatty acid synthesis and enzymatic activity of sheep adipose tissue. Journal of Nutrition 103: 1479–1488.CrossRefGoogle ScholarPubMed
Johns, J. T. and Bergen, W. G. 1976. Growth in sheep. Pre- and post-weaning hormone changes and muscle and liver development. Journal of Animal Science 43: 192–200.CrossRefGoogle ScholarPubMed
Judson, G. J., Filsell, O. H. and Jarrett, I. G. 1976. Glucose and acetate metabolism in sheep at rest and during exercise. Australian Journal of Biological Science 29: 215–222.CrossRefGoogle ScholarPubMed
Leng, R. A., Steel, J. W. and Luick, J. R. 1967. Contribution of propionate to glucose synthesis in sheep. Biochemical Journal 103: 785–790.CrossRefGoogle ScholarPubMed
Microsoft. 1985. Microsoft Fortran Reference Manual. Microsoft Corporation, Seattle.Google Scholar
Munro, H. N. 1969. Evolution of protein metabolism in mammals. In Mammalian Protein Metabolism (ed. Munro, H. N.), pp. 133–182. Academic Press, New York.CrossRefGoogle ScholarPubMed
Oltjen, J. W., Bywater, A. C. and Baldwin, R. L. 1985. Simulation of normal protein accretion in rats. Journal of Nutrition 115: 45–52.CrossRefGoogle ScholarPubMed
Oltjen, J. W., Bywater, A. C. and Baldwin, R. L. 1986a. Evaluation of a model of beef cattle growth and composition. Journal of Animal Science 62: 98–108.CrossRefGoogle Scholar
Oltjen, J. W., Bywater, A. C., Baldwin, R. L. and Garrett, W. N. 1986b. Development of a dynamic model of beef cattle growth and composition. Journal of Animal Science 62: 86–97.CrossRefGoogle Scholar
Ørskov, E. R., Grubb, D. A., Smith, J. S., Webster, A. J. F. and Corrigall, W. 1979. Efficiency of utilization of volatile fatty acids for maintenance and energy retention by sheep. British Journal of Nutrition 41: 541–551.Google Scholar
Ørskov, E. R., McDonald, I., Fraser, C. and Corse, E. L. 1971. The nutrition of the early weaned lamb. III. The effect of ad libitum intake of diets varying in protein concentration on performance and on body composition at different live weights. Journal of Agricultural Science, Cambridge 77: 351–361.CrossRefGoogle Scholar
Prior, R. L. 1978. Effect of level of feed intake on lactate and acetate metabolism and lipogenesis in vivo in sheep. Journal of Nutrition 108: 926–935.CrossRefGoogle ScholarPubMed
Pullar, J. D. and Webster, A. J. F. 1977. The energy cost of fat and protein deposition in the rat. British Journal of Nutrition 37: 355–363.CrossRefGoogle ScholarPubMed
Sainz, R. D. and Wolff, J. E. 1987. Mechanisms of action of repartitioning agents: quantitative and dynamic evaluation of alternative hypotheses. Proceedings of the 2nd International Symposium on the Nutrition of Herbivores, pp. 153–154. Australian Society of Animal Production, Brisbane.Google Scholar
Sainz, R. D. and Wolff, J. E. 1990. Evaluation of hypotheses regarding mechanisms of action of growth promotants and repartitioning agents using a simulation model of lamb metabolism and growth. Animal Production 51: 551–558.Google Scholar
Schimke, R. T. 1969. Regulation of protein degradation in mammalian tissues. In Mammalian Protein Metabolism (ed. Munro, H. N.), pp. 177–228. Academic Press, New York.Google Scholar
Sinnett-Smith, P. A., Dumelow, N. W. and Buttery, P. J. 1983. Effects of trenbolone acetate and zeranol on protein metabolism in male castrate and female lambs. British Journal of Nutrition 50: 225–234.CrossRefGoogle ScholarPubMed
Sutton, J. D. 1980. Digestion and end-product formation in the rumen from production rations. In Digestive Physiology and Metabolism in Ruminants (ed. Ruckebusch, Y. and Thivend, P.), Proceedings of the V International Symposium on Ruminant Physiology, pp. 271–308. MTP Press Ltd, Lancaster.Google Scholar
Tulloh, N. M., Brimblecombe, H. and Dennis, C. 1986. The effect of severe nutritional deprivation in early post-natal life on tissue and cellular responses during subsequent growth of lambs to the age of 4 months. Journal of Agricultural Science, Cambridge 106: 341–350.Google Scholar
Wolff, J. E. and Bergman, E. N. 1972. Gluconeogenesis from plasma amino acids in fed sheep. American Journal of Physiology 223: 455–460.Google Scholar