An analysis of the composition of gain and growth of primal cuts of Iberian pigs of 10 to 150 kg body weight as affected by the level of feeding and dietary protein concentration

Rosa Nieto, Luis Lara, Roberto Barea, Rosa García-Valverde, Jose A. Conde-Aguilera, Jose F. Aguilera Sánchez


A meta-analysis was made of data from a total of 211 growing-finishing Iberian (IB) pigs from four separate and independent sets of trials. Within each set of trials, a factorial arrangement of treatments was used, involving several concentrations of ideal protein in the diets and two or three levels of feed intake. Pigs were slaughtered at several stages of growth from 10 to 150 kg body weight (BW). The partition of dietary protein in the body of the pigs, the empty-body gain (EBG), the chemical composition of EBG, growth of primal cuts in the cold eviscerated carcass (without head, feet, and tail), and mass of dissected tissues in trimmed shoulder and ham were determined. Linear regression equations allowed estimating N requirements for maintenance as 175 mg/(kg BW0.75 · kg dry-matter intake) · d-1 and an average value for the net efficiency of utilization of the dietary protein apparently absorbed of 0.386. In pigs offered adequate protein to energy diets, EBG was predicted as a function of average BW and feeding level (p<0.001). Multiple regression equations were constructed, which derived nutrient (g kg-1) or energy (MJ kg-1) composition of EBG as a function of empty-body weight (EBW), dietary protein to energy ratio, and level of feeding (p<0.001). These predictive equations, not applicable to pigs of lean and conventional genotypes, can contribute to the design of optimal feeding strategies to improve the efficiency of IB pig production systems and to achieve high quality standards in end products for the market.


energy intake; feed restriction; protein-to-energy ratio; Iberian barrows

Full Text:




AOAC, 1990. Official methods of analysis, 15th ed. Assoc. Off. Anal. Chem., Arlington, VA, USA.

Barea R, Nieto R, Lara L, García MA, Vilchez MA, Aguilera JF, 2006. Effects of dietary protein content and feeding level on carcass characteristics and organ weights of Iberian pigs growing between 50 and 100 kg body weight. Anim Sci 82: 405-413.

Barea R, Nieto R, Aguilera JF, 2007. Effects of the dietary protein content and the feeding level on protein and energy metabolism in Iberian pigs growing from 50 to 100 kg body weight. Animal 1: 357-365.

Bikker P, 1994. Protein and lipid accretion in body components of growing pigs: Effects of body weight and nutrient intake. Doctoral thesis. Agricultural University of Wageningen, Wageningen, the Netherlands.

Bikker P, Verstegen MWA, Bosch MW, 1994. Amino acid composition of growing pig is affected by protein and energy intake. J Nutr 124: 1961-1969.

Birkett S, de Lange K, 2001. Calibration of a nutrient flow model of energy utilization by growing pigs. Br J Nutr 86: 675-689.

Black JL, Cambell RG, Williams IH, James KJ, Davies GT, 1986. Simulation of energy and amino acid utilization in the pig. Res Dev Agric 3: 121-145.

BOE, 2014. Royal Decree 4/2014, of 10 January, which approves the norm of quality for pork, and cured- hams, shoulders and loins from the Iberian pig. Boletín Oficial del Estado No. 10, pp: 1569-1585.

BSAS, 2003. Nutrient requirement standards for pigs. Pr. Soc. Anim. Sci., Penicuik, UK. 28 pp.

Campbell RG, Taverner MR, Curic DM, 1984. Effect of feeding level and dietary protein content on the growth, body composition and rate of protein deposition in pigs growing from 45 to 90 kg. Anim Prod 38: 233-240.

Campbell RG, Taverner MR, Curic DM, 1985. The influence of feeding level on the protein requirements of pigs between 20 and 45 kg liveweight. Anim Prod 40: 489-496.

Conde-Aguilera JA, Aguinaga MA, Aguilera JF, Nieto R, 2011a. Nutrient and energy retention in weaned Iberian piglets fed diets with different protein concentrations. J Anim Sci 89: 754-763.

Conde-Aguilera JA, Aguinaga MA, Lara L, Aguilera JF, Nieto R, 2011b. Carcass traits and organs weights of 10-25 kg body weight Iberian pigs fed diets with different protein-to-energy ratio. Anim Feed Sci Technol 164: 116-124.

Daza A, Olivares A, Cordero G, López-Bote CJ, 2007. Short communication. Prediction of weight of major cuts by mean slaughter or carcass weight in Iberian pigs. Span J Agric Res 5: 318-321.

de Lange CFM, Morel PCH, Birkett SH, 2003. Modeling chemical and physical body composition of the growing pig. J Anim Sci 81: E159-E165.

Dourmad JY, Guillou D, Sève B, Henry Y, 1996. Response to dietary lysine supply during the finishing period in pigs. Livest Prod Sci 45: 179-186.

Fuller MF, Franklin MF, McWilliam R, Pennie K, 1995. The responses of growing pigs, of different sex and genotype, to dietary energy and protein. Anim Sci 60: 291-298.

García-Valverde R, Barea R, Lara L, Nieto R, Aguilera JF. 2008. The effects of feeding level upon protein and fat deposition in Iberian heavy pigs. Livest Sci 114: 263-273.

Gu Y, Schinckel AP, Martin TG, 1992. Growth, development, and carcass composition in five genotypes of swine. J Anim Sci 70: 1719-1729.

Kyriazakis I, Emmans GC, McDaniel R, 1993. Whole body amino acid composition of the growing pig. J Sci Food Agric 62: 29-33.

Kyriazakis I, Emmans GC, Anderson DH, 1995. Do breeds of pig differ in the efficiency with which they use a limiting protein supply? Br J Nutr 74: 183-195.

Mahan DC, Shields RG Jr, 1998. Essential and nonessential amino acid composition of pigs from birth to 145 kilograms of body weight, and comparison to other studies. J Anim Sci 76: 513-521.

Mohn S, Gillis AM, Moughan PJ, de Lange CFM, 2000. Influence of dietary lysine and energy intakes on body protein deposition and lysine utilization in the growing pig. J Anim Sci 78: 1510-1519.

Moughan PJ, 1999. Protein metabolism in the growing pig. In: Quantitative biology of the pig (Kyriazakis I, ed.), CABI, Wallingford, UK, pp: 299-331.

Nieto R, Miranda A, García MA, Aguilera JF, 2002a. The effect of dietary protein content and feeding level on the rate of protein deposition and energy utilization in growing Iberian pigs from 15 to 50 kg body weight. Br J Nutr 88: 39-49.

Nieto R, Rivera M, García MA, Aguilera JF; 2002b. Amino acid availability and energy value of acorn in the Iberian pig. Livest Prod Sci 77: 227-239.

Nieto R, Lara L, García MA, Vílchez MA, Aguilera JF, 2003. Effects of dietary protein content and food intake on carcass characteristics and organ weights of growing Iberian pigs. Anim Sci 77: 47-56.

Nieto R, Lara L, Barea R, García-Valverde R, Aguinaga MA, Conde-Aguilera JA, Aguilera JF, 2012. Response analysis of the Iberian pig growing from birth to 150 kg body weight to changes in protein and energy supply. J Anim Sci 90: 3809-3820.

Nieto R, Lara L, Barea R, García-Valverde R, Conde-Aguilera JA, Aguilera JF, 2013. Growth of body components and carcass composition of Iberian pigs of 10 to 150 kg body weight as affected by the level of feeding and dietary protein concentration. J Anim Sci 91: 4197-4207.

NRC, 1998. Nutrient requirements of swine, 10th rev. ed. Natl. Acad. Press, Washington, DC, USA. 189 pp.

NRC, 2012. Nutrient requirements of swine. Natl. Acad. Press, Washington, DC, USA. 400 pp.

Quiniou N, Noblet J, 1995. Prediction of tissular body composition from protein and lipid deposition in growing pigs. J Anim Sci 73: 1567-1575.

Quiniou N, Dourmad JY, Noblet J, 1996. Effect of energy intake on the performance of different pig types from 45 to 100 kg body weight. 1. Protein and lipid deposition. Anim Sci 63: 277-288.

Sandberg FB, Emmans GC, Kyriazakis I, 2005. Partitioning of limiting protein and energy in the growing pig: testing quantitative rules against experimental data. Br J Nutr 93: 213-224.

Susenbeth A, 1995. Factors affecting lysine utilization in growing pigs: an analysis of literature data. Livest Prod Sci 43: 193-204.

Wagner JR, Schinckel AP, Chen W, Forres JC, Coe BL, 1999. Analysis of body composition changes of swine during growth and development. J Anim Sci 77: 1442-1466.

Wenk C, Colombani PC, van Milgen J, Lemme A, 2001. Glossary: Terminology in animal and human energy metabolism. In: Energy metabolism in animals (Chwalibog A, Jacobsen K, eds.). EAAP Publ. No. 103, Wageningen Pers, Wageningen, The Netherlands, pp: 409-421.

Wiseman TG, Mahan DC, Peters JC, Fastinger ND, Ching S, Kim YY, 2007. Tissue weights and body composition of two genetic lines of barrows and gilts from twenty to one hundred twenty-five kilograms of body weight. J Anim Sci 85: 1825-1835.

DOI: 10.5424/sjar/2014124-5934