Fatty acids composition, lipids health indices and enzyme activities of longissimus thoracis muscle of six breeds of sheep produced on pasture in Northern region of Uruguay

Abstract

The determination of fatty acids composition of glycerolipids and glycerophospholipids of meat from longissimus thoracis of six breeds of lamb produced on pasture in Uruguay was undertaken by gas chromatography. Also some lipids health indices and lipids metabolism enzymes were determined. The studied lambs were males aged of 11–12 months of breeds and biotypes Highlander® (H), Merino Dohne (MD), Corriedale (C), Corriedale Pro® (CPRO), a crossing between Corriedale × Australian Merino (C×AM) and Romney Marsh (RM). The animals were reared on pasture in identical conditions without supplementation. The grazing was rotational based on a winter annual crops oats (Avena sativa spp.), cocksfoot, (Dactylis glomerata spp.) and white clover (Trifolium repens spp.). The results of the study did not show substantial differences between breeds regarding the fatty acids composition of meat, except for few relevant fatty acids such as C16:0 (MD>C), C18:3n3 (H<C) and CLA (H<CPRO, CxAM) for glycerolipids. Also C18:1 (H>CPRO, CxAM), C18:2n6 (H<CxAM) and C18:3n3 (H<C) for glycerophospholipids. Likewise, other differences were outlined such as the anteiso monomethyl fatty acid content (MD<RM), the hypocholesterolemic/hypercholesterolemic ratio (MD<C). For lipids metabolism enzymes indices, MD showed a lower Δ–9 desaturase enzyme for C16:0 than C, CPRO and CxAM. Also, H showed a lower Δ–6 desaturase enzyme activity than C, and both MD and CxAM showed a lower elongase enzyme activity than C. The results of the present investigation showed that the meat of the lamb of the different breeds overall present good lipids nutritional indicators, in comparison with the results of other research in lambs. That information could help lamb producers in Uruguay to promote their products based on scientific data.