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Manipulating the fatty acid composition including CLA content of animal products

Manipulating the fatty acid composition including CLA content of animal products. Professor, Dr. Peter Buttery Division of Biochemistry & Nutrition Biosciences School The University of Nottingham UK. Why Manipulate the fatty acid composition of animal products?.

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Manipulating the fatty acid composition including CLA content of animal products

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  1. Manipulating the fatty acid composition including CLA content of animal products Professor, Dr. Peter Buttery Division of Biochemistry & Nutrition Biosciences School The University of Nottingham UK

  2. Why Manipulate the fatty acid composition of animal products? • To reduce the intake of “bad” fatty acids by the consumer • To increase the intake of “good” fatty acids by the consumer • To increase sales of such products by improving their “image”

  3. Dietary Reference Values for Fatty AcidsPopulation averages (% total energy)1991 Saturated Fatty Acids 10% Cis polyunsaturated fatty acids 6% Cis monounsaturated fatty acids 12% Trans fatty acids 2% Total Fatty Acids 30%

  4. Further Recommendations1994 Population average consumption of long chain n-3 polyunsaturated fatty acids should double (from 0.1g/day to 0.2g/day (not going to discus this here but is important)

  5. Saturated fatty acid (SFA) intake in Great Britain target Source: National Food Survey 2000

  6. Contribution of Animal Products to Saturated Fatty Acid (SFA) Intake in Great BritainNational Food Survey 2000 Other 39% Dairy 39% Meat 22%

  7. Meat contributes about 22% of total and saturated fat intake in the human diet • Lamb has a high stearate content which gives a waxy texture, producing poor organoleptic properties • Red meat, as part of a balanced diet, is an important source of protein and iron

  8. Possible Approaches • Change fatty acid profile of diet ~ low fat diet ~ biohydrogenation of unsaturated fat • Protected fatty acids • Manipulation of de novo fat synthesis that is reduce the fat content of the carcass

  9. Reduction of fat • Breeding • Diet • Growth Hormone * • Beta agonists* • CLA? • *Not legal in Europe but are in many parts of the world----China?

  10. Fatty acid composition of intramuscular fat in pigs fed different oils Entire male Landrace*Large White Pigs (3 per group) were grown from 55kg to 120kg LF diet: no added fat SO diet: 43.5g/kg sunflower oil + 31.5g/kg rape seed oil RO diet: 75g/kg rape seed oil Budd, Salter, Buttery & Wiseman, unpublished data

  11. THE RUMINANT • Fats over 10% cause problems with rumen function • Unsaturated fats are hydrogenated in the rumen so difficult to alter the diet.

  12. Adipose Tissue Fatty Acid Deposition in Ruminant Adipose Tissue DIET DE NOVO SYNTHESIS C18:1/C18:2/C18:3 C16:0 C18:0 C18:0 Rumen C18:1 Adipose Tissue

  13. Fatty acid composition abomasal fluid and adipose tissue of sheep fed on grass nuts

  14. Sources of Ruminant Milk Saturated Fatty Acids Mammary Gland Acetate/ -OH Butyrate C16:0 C4:0-C14:0 C18:1 C18:0 Diet Adipose Tissue

  15. Comparison of the fatty acid composition of duodenal fluid and milk from cows

  16. Fatty acid synthesis in adipose tissue & mammary gland MAMMARY ADIPOSE Acetyl CoA Acetyl CoA Acetyl CoA Carboxylase (ACC) Malonyl CA Malonyl CA Fatty Acid Synthase (FAS) C16:0 C16:0 Elongase C18:0 C18:0 Stearoyl CoA Desaturase (SCD) C18:1 C18:1

  17. Correlation between SCD mRNA and oleate content of omental adipose tissue of growing sheep

  18. Effect of insulin on SCD gene expression & oleate synthesis in ovine adipose tissue explants Ins: 20nM Insulin Dex: 10nM Dexamethosone cont ins dex ins + dex cont ins dex ins + dex

  19. Effect of feeding forage or concentrate-based diets on acetyl CoA carboxylase(ACC) & stearoyl CoA desaturase(SCD) mRNA concentrations of subcutaneous adipose tissue in sheep P<0.001

  20. Effect of feeding forage or concentrate-based diets on fatty acid composition of subucateous adipose tissue in sheep

  21. PROTECT FAT FROM RUMEN • Coat the fat so that it escapes the action of the rumen bacteria • The coat is then broken down in either abomasum or the duodenum

  22. Effect of feeding rumen- protected fish oil on the muscle fatty acid content of lot-fed cattleAshes et al (2000) Recent Advances in Animal Nutrition, 129-140

  23. Trans-10, cis 12-CLA Cis- 9, trans 11-CLA Linoleic acid

  24. Why interested in CLAs?Suggested health benefits to humans • Altered nutrient partitioning and lipid metabolism • Antiatherogenic • Anticarcinogenic • Antidiabetic (type II diabetes) • Immunity enhancement • Improved bone mineralization

  25. Production of CLAs in the rumen Linoleic Acid cis-9, cis-12 18:2 cis-9, trans-11 CLA trans-10, cis-12 CLA trans-11 18:1 trans-10 18:1 Stearic acid

  26. Rumen Adipose tissue Linoleic acid Linoleic acid c9, t11 c9, t11 SCD t11 C18:1 t11 C18:1 Stearic acid Stearic acid Production of CLA

  27. Effect of feeding forage or concentrate-based diets on the CLA content of abomassal fluid, subcutaneous adipose tissue & L. dorsi muscle of sheep cis 9, trans 11 trans 10, cis 12

  28. Seasonal variation in cis 9, trans 11-CLA content of milk

  29. SCD ACTIVITY • There is some evidence that there is genetic variation • Some cows seems to produce more CLA in the diet than others.Polymorphisms in the SCD gene? • We have not been able to find much variation in adipose tissue and liver of sheep

  30. Production of CLA-enriched butterIp et al (1999) J Nutr 129: 2135-2142 Cows fed 5.3% sunflower oil and selected for CLA production

  31. Effect of CLA on development of Mammary Cancer in rats *30 rats per group were treated with a chemical carcinogen. Values represent the number of animals with tumours adapted from Ip et al (1999) J. Nutr 129:2135-2142 + primarily cis-9, trans-10 isomer

  32. Could it be used in humans? • Rats were fed 20% (w/w) butter • Rats weighed 180g and would probably consume about 10g of food a day (2g) butter • This is equivalent to 11g butter/kg body weight/day • Thus a 70kg man would have to consume 770g butter/day to get the same amount • More research is needed • Professor Bauman in the USA working in the area

  33. Protected Not protected CLA CLA C18:0 CLA Manipulating supply of CLA to sheep tissues • Rumen saturates fatty acids therefore need to protect CLA supplement (containing equal levels c-9,t-11 and t-10,c-12) from ruminal degradation to  absorption in small intestine

  34. Rumen protected CLA Proportion of ingested CLA reaching Duodenum CLA-80 protected by Trouw Nutrition: Used matrix of saturated fat of vegetable origin and final product produced by prilling, spray drying and spray chilling. Determined to be ~ 70 % protected in cannulated sheep by dual-phase markers

  35. How much do we feed? • Ostrowska et al., (1999) • Growing pigs fed CLA-55 (mixture of both isomers) 0, 1.25, 2.5, 5, 7.5, 10g CLA/kg diet • Fat deposition decreased with increasing CLA • Fat:lean decreased with increasing CLA • Av 80 kg pig @ highest dose = 0.19 g CLA/kg body weight/day

  36. How much do we feed? • PCLA ~ 66 % effective at bypassing rumen biohydrogenation • High levels lipid adversely affect rumen function • Max amount PCLA supplied daily to small intestine of av. 40 kg lamb calculated = 0.28 kg CLA/kg BW • Predicted that lambs would consume 1 kg DM/day therefore highest PCLA inclusion was 100 g/kg DM • 25 and 50g/kg DM groups for dose response

  37. Trial Outline • 36 ewe lambs Inclusion g/kg feedGE/day (MJ) • Control (n=6) 18.42 • Low PCLA (n=5) 25 19.42 • Med PCLA (n=5) 50 19.86 • Hi PCLA (n=5) 100 21.30 • Low Megalac (n=5) 21.7 19.14 • Med Megalac (n=5) 43.3 19.86 • Hi Megalac (n=5) 86.6 21.30 • Megalac controls for lipid coating of PCLA • Fed for 10 wks, control group designed to grow at 180 g/d

  38. Sample analysis • Fatty acid composition • Did the CLA get into the animals tissues? • Carcass characteristics • Repartitioning effects of CLA?

  39. cis-9, trans-11 trans-10, cis-12 Subcutaneous CLA content

  40. cis-9, trans-11 trans-10, cis-12 Omental CLA content

  41. cis-9, trans-11 trans-10, cis-12 Perirenal CLA content

  42. cis-9, trans-11 trans-10, cis-12 L. dorsi CLA content

  43. cis-9, trans-11 trans-10, cis-12 Liver CLA content

  44. Effect of dietary CLA on carcass fat

  45. Carcass characteristics • No change in carcass composition • Carcass cold weight • Back fat thickness • Omental and perirenal depot whole weights • Muscle weight (L. Dorsi, V. Lateralis, S. Tendenosus) • Eye muscle depth or width • Liver weight BUT definite incorporation of CLA into tissues

  46. Accumulation of CLA(t10,c12) in subcutaneous adipose tissue Pig data: adapted from Ostrowska et al (2003)

  47. Effect of dietary CLA on carcass fat PIGS SHEEP Adapted from Ostrowska et al (2003) *Corrected for protection

  48. Conclusion • Tissue CLA content increased but no effect on carcass • Maybe ruminant adipose tissue responds differently to monogastrics?

  49. Conclusions • Animal products continue to supply a major proportion of dietary saturated fatty acids • SCD plays a major role in determining the nature of fatty acids synthesized in tissues • It is possible to increase the concentration of “healthy” fatty acids (e.g. n-3 PUFA & CLA) in meat & dairy produce but whether the changes can be great enough to have a significant impact on human health remains to be established

  50. Acknowledgement • Professor Andrew Salter • Dr Sean Richards • Dr Zoe Daniel • Dr Richard Wynn

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