Effects of dietary n-3 polyunsaturated fatty acids and ... - FINS

1 st WorkshopXIII International Feed Technology SymposiumCONCLUSIONIn meat producing cattle, addition of n-3 PUFA (from extruded linseed) in dietsimproved the nutritional value of beef by favouring incorporation of 18:3n-3 and otherLC n-3 PUFA (EPA, DPA) in muscle tissues, especially in phospholipids of cellmembranes. Moreover, such a nutritional strategy would also favour deposition ofconjugated linoleic acid (CLA) especially the rumenic acid (9cis,11trans 18:2) and itsprecursor, the vaccenic acid (18:1Δ11trans), beneficial for the health of human by theirhypocholesterolemic action.On the other hand, addition of rapeseed (rich in 18:1 n-9cis) together with linseed (richin 18:3n-3) would limit incorporation of 18:3n-3 in muscles and favour deposition oftrans isomers of 18:1 known to be detrimental for human health (18:1Δ9trans andespecially 18:1Δ10trans).High levels of dietary n-3 PUFA absorbed by animals stimulated lipoperoxidation i) inits whole body, leading to a risk of alteration of tissue and organ functions (oxidizingstress) with negative consequences on the animal welfare and health, ii) in their muscletissues where oxidized products (MDA, HHE, HNE) were deposited, altering thenutritional value of beef products for consumers. To avoid lipoperoxidation processes inanimals given n-3 PUFA from oleaginous seeds, the present work clearly showed thatvitamin E added to diets was less active than the dietary mixture composed of vitamin Eand plant polyphenols (PERP). The dietary strategy combining n-3 PUFA and theantioxidant mixture added to diets would avoid major risks of lipoperoxidation in beefproducts whatever i) the conditions of meat ageing and packaging (especially those withcontact with oxygen), 2) the level of stress of animals prior slaughter.Additionally, such dietary strategy based on the use of dietary vitamin E and plantpolyphenol supplements would also avoid alteration of beef colour (notably in stressedanimals) which paralleled tissue lipoperoxidation. It would play a positive role in thestability of meat, an element very beneficial for meat processing industries to betterdefine their strategies in terms of meat production and transformations .REFERENCES1. Bauchart D., Gladine C., Gruffat D., Leloutre L., Durand D. 2005. Effectsof diets supplemented with oils and vitamin E on specific fatty acids of rectusabdominis muscle in charolais fattening bulls. In "Indicators of milk and beefquality", EAAP Publ. n°112, (editors J F Hocquette and S Gigli), WageningenAcad. Publishers, pp 431-436.2. Bauchart D., Roy A., Lorenz S., Ferlay A., Gruffat D., Chardigny J.M.,Sébédio J.L., Chilliard Y., Durand D. 2007. Dietary supply of butter rich intrans 18:1 isomers or in 9cis, 11trans conjugated linoleic acid affects plasmalipoproteins in hypercholesterolemic rabbits. Lipids, 42, 123-133.3. Bispo Villar, E, Thomas A., Lyan B., Gruffat D., Durand D., Bauchart D.2009. Lipid supplements rich in n-3 polyunsaturated fatty acids deeply modifytrans 18:1 isomers in the Longissimus thoracis muscle of finishing bovine. Inthe Proceedings of the 11th International Symposium on Ruminant Physiology,6-9th September 2009, Clermont-Ferrand, France10