Feed Energy Evaluation for Growing Pigs

  • Kil, D.Y. ;
  • Kim, B.G. ;
  • Stein, H.H.
  • Published : 2013.09.01


Pigs require energy for maintenance and productive purposes, and an accurate amount of available energy in feeds should be provided according to their energy requirement. Available energy in feeds for pigs has been characterized as DE, ME, or NE by considering sequential energy losses during digestion and metabolism from GE in feeds. Among these energy values, the NE system has been recognized as providing energy values of ingredients and diets that most closely describes the available energy to animals because it takes the heat increment from digestive utilization and metabolism of feeds into account. However, NE values for diets and individual ingredients are moving targets, and therefore, none of the NE systems are able to accurately predict truly available energy in feeds. The DE or ME values for feeds are important for predicting NE values, but depend on the growth stage of pigs (i.e., BW) due to the different abilities of nutrient digestion, especially for dietary fiber. The NE values are also influenced by both environment that affects NE requirement for maintenance ($NE_m$) and the growth stage of pigs that differs in nutrient utilization (i.e., protein vs. lipid synthesis) in the body. Therefore, the interaction among animals, environment, and feed characteristics should be taken into consideration for advancing feed energy evaluation. A more mechanistic approach has been adopted in Denmark as potential physiological energy (PPE) for feeds, which is based on the theoretical biochemical utilization of energy in feeds for pigs. The PPE values are, therefore, believed to be independent of animals and environment. This review provides an overview over current knowledge on energy utilization and energy evaluation systems in feeds for growing pigs.


Energy Utilization;Feed Energy Systems;Pigs


  1. Ayoade, D. I., E. Kiarie, M. A. Trinidade Neto, and C. M. Nyachoti. 2012. Net energy of diets containing wheat-corn distillers dried grains with solubles as determined by indirect calorimetry, comparative slaughter, and chemical composition methods. J. Anim. Sci. 90:4373-4379.
  2. Bakker, G. C. M. 1996. Interaction between carbohydrates and fat in pigs. Ph.D. Thesis, University of Wageningen, Wageningen, The Netherlands.
  3. Baldwin, R. L. 1995. Energy requirements for maintenance and production. In: Modeling Ruminant Digestion and Metabolism. (Ed. R. L. Baldwin). Chapman and Hall, London, UK. pp. 148-188.
  4. Baldwin, R. L. and A. C. Bywater. 1984. Nutritional energetics of animals. Annu. Rev. Nutr. 4:101-114.
  5. Birkett, S. and K. de Lange. 2001. Limitations of conventional models and a conceptual framework for a nutrient flow representation of energy utilization by animals. Br. J. Nutr. 86:647-659.
  6. Black, J. L. 1995. Modelling energy metabolism in the pig - critical evaluation of a simple reference model. In: Modelling Growth in the Pig (Ed. P. J. Moughan, M. W. A. Verstegen, and M. I. Visser-Reyneveld). Wageningen Press, Wageningen, The Netherlands. pp. 87-102.
  7. Black, J. L. 2000. Bioavailability: the energy component of a ration for monogastric animals. In: Feed Evaluation: Principle and Practice (Ed. P. J. Moughan, M. W. A. Verstegen, and M. I. Visser-Reyneveld). Wageningen Press, Wageningen, The Netherlands. pp. 133-152.
  8. Black, J. L. and C. F. M. de Lange. 1995. Introduction to the principles of nutrient partitioning for growth. In: Modelling Growth in the Pig (Ed. P. J. Moughan, M. W. A. Verstegen, and M. I. Visser-Reynevel). Wageningen Press, Wageningen, The Netherlands. pp. 115-122.
  9. Blaxter, K. L. 1989. Energy metabolism in animals and man. Cambridge University Press, Cambridge, UK.
  10. Blok, M. C. 2006. Development of a new net energy formula by CVB, using the database of INRA. Int. Sym. Proc. Net energy systems for growing and fattening pigs. Vejle, Denmark. pp. 40-57.
  11. Boisen, S. 2007. New concept for practical feed evaluation systems. DJF Animal Science No. 79. Research Centre Foulum, Denmark.
  12. Boisen, S. and M. W. A. Verstegen. 2000. Developments in the measurement of the energy content of feeds and energy utilisation in animals. In: Feed evaluation: principle and practice (Ed. P. J. Moughan, M. W. A. Verstegen, and M. I. Visser-Reyneveld). Wageningen Press, Wageningen, The Netherlands. pp. 57-76.
  13. Bray, H. J., L. R. Giles, J. M. Gooden, and J. L. Black. 1997. Energy expenditure in growing pigs infected with pleuropneumonia. In: Energy Metabolism of Farm Animals (Ed. K. J. McCracken, E. F. Unsworth, and A. R. G. Wylie). Proceedings of the 14th Symposium on Energy Metabolism, Newcastle, Northern Ireland. pp. 291-294.
  14. Brown, D. 1982. The metabolic body size of the growing pig. Livest. Prod. Sci. 9:389-398.
  15. Chwalibog, A. 1991. Energetics of animal production. Acta Agric. Scand. 41:147-160.
  16. Close, W. H. 1996. Modelling the growing pig: Predicting nutrient needs and responses. In: Biotechnology in the Feed Industry. The living gut: Bridging the gap between nutrition and performance (Ed. T. P. Lyons and K. A. Jacques). Proc. Alltech's 12th Annual Symposium. Nottingham University Press, Nottingham, UK. pp. 289-297.
  17. Cozannet, P., Y. Primot, C. Gady, J. P. Metayer, M. Lessire, F. Skiba, and J. Noblet. 2010. Energy value of wheat distillers grains with solubles for growing pigs and adult sows. J. Anim. Sci. 88:2382-2392.
  18. de Goey, L. W. and R. C. Ewan. 1975. Energy values of corn and oats for young swine. J. Anim. Sci. 40:1052-1057.
  19. de Greef, K. H., M. W. A. Verstegen, B. Kemp, and P. L. van der Togt. 1994. The effect of body weight and energy intake on the composition of deposited tissue in pigs. Anim. Prod. 58:263-270.
  20. de Lange, C. F. M. 2008. Efficiency of utilization of energy from protein and fiber in the pig- A case for NE systems. In: Proc. Midwest Swine Nutr. Conf., Indianapolis, IN. pp. 58-72.
  21. de Lange, C. F. M. and S. H. Birkett. 2005. Characterization of useful energy content in swine and poultry feed ingredients. Can. J. Anim. Sci. 85:269-280.
  22. de Lange, C. F. M., J. van Milgen, J. Noblet, S. Dubois, and S. Birkett. 2006. Previous feeding level influences plateau heat production following a 24 h fast in growing pigs. Br. J. Nutr. 95:1082-1087.
  23. Emmans, G. C. 1999. Energy flows. In: A Quantitative Biology of the Pig (Ed. I. Kyriazakis). CABI Publishing, Wallingford, U. K. pp. 363-377.
  24. Ewan, R. C. 2001. Energy utilization in swine nutrition. In: Swine Nutrition, 2nd Ed. (Ed. A. J. Lewis and L. L. Southern). CRC Press, Washington, DC. pp. 85-94.
  25. Giles, L. R., M. L. Lorschy, H. J. Bray, and J. L. Black. 1998. Predicting feed intake in growing pigs. In: Progress in Pig Science (Ed. J. Wiseman, M. A. Varley, and J. P. Chadwick). Nottingham University Press, Nottingham, U.K. pp. 209-228.
  26. Just, A. 1982. The net energy value of balanced diets for growing pigs. Livest. Prod. Sci. 8:541-555.
  27. Just, A., H. Jorgensen, and J. A. Fernandez. 1983. Maintenance requirement and the net energy value of different diets for growth in pigs. Livest. Prod. Sci. 10:487-506.
  28. Kil, D. Y. 2008. Digestibility and energetic utilization of lipids by pigs. Ph.D. Thesis, University of Illinois, Urbana, USA.
  29. Kil, D. Y., F. Ji, L. L. Stewart, R. B. Hinson, A. D. Beaulieu, G. L. Allee, J. F. Patience, J. E. Pettigrew, and H. H. Stein. 2011. Net energy of soybean oil and choice white grease in diets fed to growing and finishing pigs. J. Anim. Sci. 89:448-459.
  30. Kil, D. Y., F. Ji, L. L. Stewart, R. B. Hinson, A. D. Beaulieu, G. L. Allee, J. F. Patience, J. E. Pettigrew, and H. H. Stein. 2013. Effects of dietary soybean oil on pig growth performance, retention of protein, lipids, and energy, and on the net energy of corn in diets fed to growing or finishing pigs. J. Anim. Sci. 91:3283-3290.
  31. Kleiber, M. 1975. The fire of life, 2nd Ed. (Ed. R. E. Krieger), New York, NY.
  32. Knap, P. 2000. Variation in maintenance requirements of growing pigs in relation to body composition. A simulation study. Ph. D. Thesis, University of Wageningen, Wageningen, The Netherlands.
  33. Koong, L. J., J. A. Nienaber, and H. J. Mersmann. 1983. Effects of plane of nutrition on organ size and fasting heat production in genetically obese and lean pigs. J. Nutr. 113:1626-1631.
  34. Le Bellego, L., J. van Milgen, S. Dubois, and J. Noblet. 2001. Energy utilization of low-protein diets in growing pigs. J. Anim. Sci. 79:1259-1271.
  35. Le Goff, G. and J. Noblet. 2001. Comparative total tract digestibility of dietary energy and nutrients in growing pigs and adult sows. J. Anim. Sci. 79:2418-2427.
  36. Lizardo, R., J. van Milgen, J. Mourot, J. Noblet, and M. Bonneau. 2002. A nutritional model of fatty acid composition in the growing-finishing pig. Livest. Prod. Sci. 75:167-182.
  37. McDonald, P., R. A. Edwads, J. F. D. Greenhalgh, and C. A. Morgan. 2002. Evaluation of foods: energy content of foods and the partition of food energy within the animal. In: Animal Nutrition. 5th Ed. (Ed. P. McDonals, R. A. Edwads, J. F. D. Greenhalgh, and C. A. Morgan). Pearson, UK. pp. 263-291.
  38. Mayes, P. A. 2000. Bioenergetics: The role of ATP. In: Harper's Biochemistry, 25th Ed. (Ed. R. K Murry, D. K. Granner, P. A. Mayes, and V. W. Rodwell). McGraw-Hill, New York, NY. pp. 123-129.
  39. Moehn, S., J. Atakora, and R. O. Ball. 2005. Using net energy for diet formulation: Potential for the Canadian pig industry. Adv. Pork Prod. 16:119-129.
  40. Morgan, D. J., D. J. A. Cole, and D. Lewis. 1975. Energy values in pig nutrition: I. The relationship between digestible energy, metabolizable energy and total digestible nutrient values of a range of feedstuffs. J. Agric. Sci. (Camb.). 84:7-17.
  41. Noblet, J. 1996. Digestive and metabolic utilization of dietary energy in pig feeds: Comparison of energy systems. In: Recent Advances in Animal Nutrition (Ed. P. C. Garnsworthy, J. Wiseman and W. Haresign). Nottingham University Press, Nottingham, U.K. pp. 207-231.
  42. Noblet, J. 2007. Recent developments in net energy research for swine. Adv. Pork Prod. 18:149-156.
  43. Noblet, J., H. Fortune, X. S. Shi, and S. Dubois. 1994a. Prediction of net energy value of feeds for growing pigs. J. Anim. Sci. 72:344-353.
  44. Noblet, J. and Y. Henry. 1993. Energy evaluation systems for pig diets: a review. Livest. Prod. Sci. 36:121-141.
  45. Noblet, J., C. Karege, and S. Dubois. 1991. Influence of growth potential on energy requirements for maintenance in growing pigs. In: Energy Metabolism of Farm Animals (Ed. C. Wenk and M. Boessinger). EAAP Publication, Zurich, Switzerland. pp. 107-110.
  46. Noblet, J., C. Karege, S. Dubois, and J. van Milgen. 1999. Metabolic utilization of energy and maintenance requirements in growing pigs: Effects of sex and genotype. J. Anim. Sci. 77:1208-1216.
  47. Noblet, J. and J. M. Perez. 1993. Prediction of digestibility of nutrients and energy values of pig diets from chemical analysis. J. Anim. Sci. 71:3389-3398.
  48. Noblet, J., X. S. Shi, and S. Dubois. 1994b. Effect of body weight on net energy value of feeds for growing pigs. J. Anim. Sci. 72:648-657.
  49. Noblet, J. and J. van Milgen. 2004. Energy value of pig feeds: Effect of pig body weight and energy evaluation system. J. Anim. Sci. 82(E. Suppl.):E229-E238.
  50. NRC. 1998. Nutrient requirements of swine. 10th rev. Ed. Natl. Acad. Press, Washington, DC.
  51. NRC. 2012. Nutrient requirements of swine. 11th rev. Ed. Natl. Acad. Press, Washington, DC.
  52. Nyachoti, C. M., R. T. Zijlstra, C. F. M. de Lange, and J. F. Patience. 2004. Voluntary feed intake in growing-finishing pigs: A review of the main determining factors and potential approaches for accurate predictions. Can. J. Anim. Sci. 84:549-566.
  53. Oresanya, T. F., A. D. Beaulieu, and J. F. Patience. 2008. Investigations of energy metabolism in weanling barrows: The interaction of dietary energy concentration and daily feed (energy) intake. J. Anim. Sci. 86:348-363.
  54. Payne, R. L. 2006. The net energy system in swine- How can it help you? Feedstuffs. March. 27:16-20.
  55. Patience, J. F. and A. D. Beaulieu. 2005. The merits, benefits, and challenges of adopting the net energy system in a North American context. In: Proc. 66th Minnesota Nutr. Conf. Tech. Symp.: Future of corn in animal feed. September 20-21. St. Paul. MN. pp. 134-149.
  56. Quiniou, N., S. Dubois, and J. Noblet. 1995. Effect of dietary crude protein level on protein and energy balances in growing pigs: comparison of two measurement methods. Livest. Prod. Sci. 41:51-61.
  57. Reynolds, C. K. 2000. Measurement of energy metabolism. In: Feeding Systems and Feed Evaluation Models (Ed. M. K. Theodorou, and J. France). CAB International, Oxon, U.K. pp. 87-107.
  58. Rijnen, M. M. J. A. 2003. Energetic utilization of dietary fiber in pigs. Ph.D. Thesis, University of Wageningen, Wageningen, the Netherlands.
  59. Rijnen, M. M. J. A., J. Doorenbos, J. J. Mallo, and L. A. den Hartog. 2004. The application of the net energy system for swine. In: Proc. Western Nutr. Conf., Saskatoon, Canada. pp. 151-168.
  60. Robles, A. and R. C. Ewan. 1982. Utilization of energy of rice and rice bran by young pigs. J. Anim. Sci. 55:572-577.
  61. Sauvant, D., J. M. Perez, and G. Tran. 2004. Tables of composition and nutritional value of feed materials: Pig, poultry, sheep, goats, rabbits, horses, and fish. Wageningen Academic Publishers, Wageningen, the Netherlands and INRA ed. Paris, France.
  62. Schiemann, R., K. Nehring, L. Hoffmann, W. Jentsch, and A. Chudy. 1972. Energetische Futterbevertung und Energienormen. VEB Deutscher Landwirtschaftsverlag, Berlin.
  63. Shi, X. S. and J. Noblet. 1993. Contribution of the hindgut to digestion of diets in growing pigs and adult sows: effect of diet composition. Livest. Prod. Sci. 34:237-252.
  64. Stewart, L. L., D. Y. Kil, F. Ji, R. B. Hinson, A. D. Beaulieu, G. L. Allee, J. F. Patience, J. E. Pettigrew, and H. H. Stein. 2013. Effects of dietary soybean hulls and wheat middlings on body composition, nutrient and energy retention, and the net energy of diets and ingredients fed to growing and finishing pigs. J. Anim. Sci. 91:2756-2765.
  65. Tess, M. W., G. E. Dickerson, J. A. Nienaber, and C. L. Ferrell. 1984. The effects of body composition on fasting heat production in pigs. J. Anim. Sci. 58:99-110.
  66. Tess, M. W., G. E. Dickerson, J. A. Nienaber, and C. L. Ferrell. 1986. Growth, development and body composition in three genetic stocks of swine. J. Anim. Sci. 62:968-979.
  67. Thonney, M. L., R. W. Touchberry, R. D. Goodrich, and J. C. Meiske. 1976. Intraspecies relationship between fasting heat production and body weight: A reevaluation of W.75. J. Anim. Sci. 43:692-704.
  68. van Milgen, J., J. F. Bernier, Y. Lecozler, S. Dubois, and J. Noblet. 1998. Major determinants of fasting heat production and energetic cost of activity in growing pigs of different body weight and breed/castration combination. Br. J. Nutr. 79:509-517.
  69. van Milgen, J. and J. Noblet. 2000. Modelling energy expenditure in pigs. In: Modelling Nutrient Utilization in Farm Animals (Ed. J. P. McNamara, J. France, and D. E. Beever). CAB International, Oxon, U. K. pp. 103-114.
  70. van Milgen, J. and J. Noblet. 2003. Partitioning of energy intake to heat, protein, and fat in growing pigs. 81(E. Suppl. 2):E86-E93.
  71. van Milgen, J., A. Valancogne, S. Dubois, J. Y. Dourmad, B. Seve, and J. Noblet. 2008. InraPorc: A model and decision support tool for the nutrition of growing pigs. Anim. Feed Sci. Technol. 143:387-405.
  72. Verstegen, M. W. A. 2001. Developments towards net energy systems in feeds and animals. Western Nutr. Conf., Saskatoon, Canada. pp. 170-184.
  73. Whittemore, C. T. 1997. An analysis of methods for the utilisation of net energy concepts to improve the accuracy of feed evaluation in diets for pigs. Anim. Feed Sci. Technol. 68:89-99.
  74. Whittemore, C. T., M. J. Hazzledine, and W. H. Close. 2003. Nutrient requirement standards for pigs. British Society of Animal Science. Penicuik.
  75. Wu, Z., D. Li, Y. Ma, Y. Yu, and J. Noblet. 2007. Evaluation of energy systems in determining the energy cost of gain of growing-finishing pigs fed diets containing different levels of dietary fat. Arch. Anim. Nutr. 61:1-9.

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