Dietary Conjugated Linoleic Acid Can Decrease Backfat in Pigs Housed under Commercial Conditions

  • Dunshea, F.R. (Agriculture Victoria, Victorian Institute of Animal Science) ;
  • Ostrowska, E. (Agriculture Victoria, Victorian Institute of Animal Science) ;
  • Luxford, B. (Bunge Meat Industries) ;
  • Smits, R.J. (Bunge Meat Industries) ;
  • Campbell, R.G. (Bunge Meat Industries) ;
  • D'ouza, D.N. (Agriculture WA) ;
  • Mullan, B.P. (Agriculture WA)
  • Received : 2001.10.16
  • Accepted : 2002.02.15
  • Published : 2002.07.01


Conjugated linoleic acids (CLA) have been shown to decrease body fat content of individually-housed pigs but little is known about the responses under commercial conditions. Two studies were conducted to evaluate the effect of CLA under commercial conditions using contemporary genotypes. The experimental designs were similar between the two sites. Briefly, the studies were 2${\times}$2 factorial designs with the respective factors being sex (boar and gilt) and supplemental dietary CLA (0 and 4 g/kg). The studies involved 16-20 pens of pigs with 4-5 pens of each sex${\times}$CLA group. The first study was conducted with 144 pigs in 16 pens consuming a pelleted feed for 6 weeks at Bunge Meat Industries, Corowa, NSW. In the second study, 160 pigs were obtained from a commercial source and put into 20 pens in simulated commercial conditions and fed a mash diet for 7 weeks at Medina Research Station, WA. In Study 2 some aspects of meat quality were also investigated. Data from Study 1 showed that, although CLA had no significant effect upon feed intake and daily gain, the small changes in both resulted in a reduction in (-0.10 g/g, p=0.10) feed conversion ratio (FCR). While there was no significant effect of CLA on ultrasonic backfat depths, there was a significant decrease in carcass P2 (-1.0 mm, p=0.014) and estimated carcass fat (-7 g/kg, p=0.049). In the study conducted at Medina CLA had no significant effect upon feed intake, feed:gain or most measures of back fat. The exception was that dietary CLA decreased the rate of accumulation of fat at the shoulder, particularly in gilts, resulting in a significantly lower amount of shoulder fat at slaughter (-1.3 mm, p=0.044). CLA tended to increase dressing percentage although this was not significant (+0.5%, p=0.14). Meat from CLA treated pigs tended to be darker (p=0.12) and had a higher ultimate pH (p=0.06). These data suggest that under commercial conditions dietary CLA can improve growth performance and decrease P2 in pigs of an improved genotype, particularly gilts.


Growth;Meat Quality;Sex;CLA;Pig


Supported by : Pig Research and Development Corporation


  1. Baker, D. H., A. Aumaitre, B. D. Lee and J. K. Ha. 2000. Recent advances in use of the ideal protein concept for swine feed formulation. Asian-Aus. J. Anim. Sci. 13:294-301.
  2. Beattie, V. E., R. N. Weatherup, B. W. Moss and N. Walker. 1999. The effect of increasing carcass weight of finishing boars and gilts on joint composition and meat quality. Meat Sci. 52:205-211.
  3. Campbell, R. G. and M. R. Taverner. 1988. Genotype and sex effects on the relationship between energy intake and protein deposition in growing pigs. J. Anim Sci. 66:76-686.
  4. Cronin, G. M., F. R. Dunshea, P. H. Hemsworth, J. L. Barnett, I. McCauley, K. L. Butler and R. J. Smits. 2001. The behaviour of group-housed, male finisher pigs. In Manipulating Pig Production VIII (Ed. P. D. Cranwell). Australasian Pig Science Association: Werribee, Australia, p. 49.
  5. Dunshea, F. R., I. McCauley, G. M. Cronin, J. L. Barnettt, P. H. Hemsworth, R. H. King, R. G. Campbell, R. J. Smits, B. Luxford, D. P. Hennessy, K. L. Butler and A. J. Tilbrook. 2000. Improving the performance/efficiency of entire male pigs under commercial conditions. Final Report DV160/1344, Pig Research and Development Corporation, Canberra.
  6. Fernandez, X., M. C. Meunier-Salaun and P. Ecolan. 1994. Glycogen depletion according to muscle and fibre types in response to dyadic encounters in pigs (Sus scrofa domesticus) relationships with plasma epinephrine and aggressive behaviour. Comp. Biochem. Physiol. A 109:869-879.
  7. Ha, Y. L., N. K. Grimm and M. W. Pariza. 1987. Anticarcinogens from fried ground beef: heat-altered derivatives of linoleic acid. Carcinogenesis 8:1881-1887.
  8. Ostrowska, E., M. Muralitharan, R. F. Cross, D. E. Bauman and F. R. Dunshea. 1999. Dietary conjugated linoleic acids increase lean tissue and decrease fat deposition in growing pigs. J. Nutr. 129:2037-2042.
  9. Park, Y., K. J. Albright, W. Liu, J. M. Storkson, M. E. Cook and M. W. Pariza. 1997. Effect of conjugated linoleic acid on body composition in mice. Lipids 32:853-858.
  10. Thiel, R. L., J. C. Sparks, B. R. Weigand, F. C. Parrish Jr and R. C. Ewan. 1998. Conjugated linoleic acid improves performance and body composition in swine. J. Anim. Sci. 76:(Suppl. 2)61 (Abstr.).
  11. Warner, R. D., R. G. Kauffman and R. L. Russell. 1993. Quality attributes of major porcine muscles: A comparison with the Longissimus lumborum. Meat Sci. 33:359-372.
  12. Dugan, M. E. R., J. L. Aalhus, A. L. Schaefer and J. K. G. Kramer. 1997. The effect of conjugated linoleic acid on fat to lean repartitioning and feed conversion in pigs. Can. J. Anim. Sci. 77:723-725.
  13. Yang, L., L. K. Leung, Y. Huang and Z. Y. Chen. 2000. Oxidative stability of conjugated linoleic acid isomers. J. Agr. Food Chem. 48:3072-3076.
  14. Dugan, M. E. R., J. L. Aalhus, L. E. Jeremiah, J. K. G. Kramer and A. L. Schaefer. 1999. The effects of feeding conjugated linoleic acid on subsequent pork quality. Can. J. Anim Sci. 79:45-51.
  15. Houseknecht, K. L., J. P. Vanden Heuvel, S. Y. Moya-Camarena, C. P. Portocarrero, L. W. Peck, K. P. Nickel and M. A. Belury. 1998. Dietary conjugated linoleic acid normalizes impaired glucose tolerance in the Zucker diabetic fatty fa/fa rat. Biochem. Biophys. Res. Commun. 244:678-682.
  16. Honikel, K. O. 1987. How to measure the water-holding capacity of meat. Recommendation of standardised methods. In Evaluation and Control of Meat Quality in Pigs (Ed. P. V. Tarrant, G. Eikelenboom and G. Monin). Martinus Nijhoff Publishers: Dordrecht. pp. 129-142.
  17. Nicolosi, R. J., E. J. Rogers, D. Kritchevsky, J. A. Scimeca and P. J. Huth. 1997. Dietary conjugated linoleic acid reduces plasma lipoproteins and early aortic atherosclerosis in hypercholesterolemic hamsters. Artery 22:266-277.
  18. Weatherup, R. N., V. E. Beattie, B. W. Moss, D. J. Kilpatrick and N. Walker. 1998. The effect of increasing slaughter weight on the production performance and meat quality of finishing pigs. Anim. Sci. 67:591-600.
  19. Belury, M. A. 1995. Conjugated dienoic linoleate: A polyunsaturated fatty acid with unique chemical properties. Nutr. Rev. 53:83-89.
  20. Pariza, M. W., Y. Park and M. E. Cook. 2001. The biologically active isomers of conjugated linoleic acid. Prog. Lipid Res. 40:283-298.
  21. Banni, S. and J. C. Martin. 1998. Conjugated linoleic acid and metabolites. In: Trans Fatty Acids in Human Nutrition. (Ed. J. L. Sebedio and W. W Christie). The Oily Press, Dundee. pp. 261-302.
  22. Dunshea, F. R., R. H. King, R. G. Campbell, R. D. Sainz and Y. S. Kim. 1993. Interrelationships between gender and ractopamine on protein and lipid deposition in rapidly-growing pigs. J. Anim. Sci. 71:2919-2930.
  23. Dunshea, F. R., P. J. Eason, R. H. King and R. G. Campbell. 1998. Interrelationships between dietary ractopamine, dietary energy and sex on protein and fat deposition in growing pigs. Aust. J. Agric. Res. 49:565-574.
  24. Ostrowska, E., F. R. Dunshea, M. Muralitharan and R. F. Cross. 2000. Comparison of silver-ion high-performance liquid chromatographic quantification of free and methylated conjugated linoleic acids. Lipids 35:1147-1153.
  25. Ip C., S. Banni, E. Angioni, G. Carta, J. McGinley, H. J. Thompson, D. Barbano and D. Bauman. 1999. Conjugated linoleic acidenriched butter fat alters mammary gland morphogenesis and reduces cancer risk in rats. J. Nutr. 129: 2135-2142.
  26. O'uinn, P. R., I. I. Smith, J. L. Nelssen, M. D. Tokach, R. D. Goodband and K. Q. Owen. 2000. A comparison of modified tall oil and conjugated linoleic acid on growing-finishing pig growth performance and carcass characteristics. J. Anim. Sci. 78:2359-2368.
  27. West, D. B., J. P. Delany, P. M. Camet, F. Blohm, A. A. Truett and J. Simeca. 1998. Effects of conjugated linoleic acid on body fat and energy metabolism in the mouse. Am. J. Physiol. 275:R667-672.
  28. Dunshea, F. R. and E. O. Ostrowska. 1999. Conjugated linoleic acid-Snake oil or wonder fat. Recent Advances in Animal Nutrition in Australia 12:159-166.
  29. Chin, S. F., J. M. Storkson, K. J. Albright, M. E. Cook and M. W. Pariza. 1994. Conjugated linoleic acid is a growth factor for rats as shown by enhanced weight gain and improved feed efficiency. J. Nutr. 124:2344-2349.
  30. Miller C. C., Y. Park, M. W. Pariza and M. E. Cook. 1994. Feeding conjugated linoleic acid to animals partially overcomes catabolic responses due to endotoxin injection. Biochem. Biophys. Res. Commun. 198:1107-1112.
  31. D'ouza, D. N., F. R. Dunshea, B. J. Leury and R. D. Warner. 1999. Effect of mixing boars during lairage and pre-slaughter handling on pork quality. Aust. J. Agric. Res. 50:109-113.
  32. Sather, A. P., S. D. M. Jones, E. J. Squires, A. L. Schaefer, W. M. Robertson, A. K. W. Tong and S. Zawadski. 1995. Antemortem handling effects on the behaviour, carcass yield and meat quality of market weight entire male pigs. Can J. Anim. Sci. 75:45-56.

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