Influence of diet on fatty acids and tocopherols in M. longissimus dorsi from reindeer

Our aim was to compare the effects of two pelleted diets containing differing FA composition with natural lichen pasture on reindeer's meat FA composition. In addition we wanted to increase the knowledge about reindeer FA metabolism and the effect of animal sex and age on FA composition in reindeer muscle. The trial included five reindeer groups: three grazing, consisting of adult males, adult females, and calves; and two groups of calves fed conventional pellets (CPD) and pellets containing crushed linseed (LPD), respectively, for two months before slaughter. Differences between male and female animals were mainly found in the neutral lipid fraction and related to fatness. Calves differed significantly from adult males and females in FA and lipid class composition. CPD led to a higher ratio of n-6 to n-3 FA compared with grazing. The ratio n-6/n-3 in the polar lipid (PL) fraction of the animals fed LPD was slightly, but not significantly, higher than that in the grazing reindeer. LPD-fed animals had lower proportions of long-chain polyunsaturated FA (LCPUFA), namely 20:4n-6, 22:5n-3, and 22:6n-3, in the PL fraction compared with the grazing animals due to the content of these FA in the natural feed. The animals seemed unable to elongate dietary FA in significant amounts. We conclude that by adding crushed linseed to the pellets it was possible to keep the favorable FA composition of meat from grazing reindeer with regard to the n-6/n-3 ratio but not in LCPUFA.