Effects of α-linolenic acid and eicosapentaenoic acid from linseed and algae, respectively, on reindeer (Rangifer tarandus tarandus L.) muscle fatty acid composition

Abstract

In an earlier study, we concluded that pellet-fed reindeer could not elongate 18:3n − 3 (α-linolenic acid – ALA) sufficiently towards long-chain polyunsaturated fatty acids (LC PUFA) and need supplementation of LC PUFA. The present work investigated that the addition of n − 3 LC PUFA to feed in combination with ALA would increase the LC PUFA in the meat. Two groups of reindeer were fed pellets containing either linseed cake or linseed cake combined with algae (Nannochloropsis oculata) for 6 weeks before slaughter. Dietary n − 6/n − 3 ratio had a distinct influence on meat fatty acid (FA) composition when comparing linseed and linseed algae-fed animals with animals fed a conventional diet. Increased dietary proportions of ALA and eicosapentaenoic acid (EPA) increased these FA in muscle and docosapentaenoic acid (DPA) and docosahexaenoic acid in the polar lipid fraction compared to the conventional-fed animals. We concluded that an increased proportion of dietary EPA might lead to an increased elongation towards DPA in muscle. Algae and linseed are possible additives to reindeer feed in order to assure a similar valuable FA composition as in pasturing animals.

Keywords:

• DHA
• GLC
• lipid metabolism
• nutrition
• ω–3 fatty acids
• sensory

Acknowledgements

The authors wish to thank Svenska Lantmännen and their representatives Sven Hellberg and Åke Strömberg for the production of the pellets, financial support and advice during the study. We are grateful to the staff at Grundnäs Kött AB for their assistance with the collection of samples and to reindeer herder Peter Omma for all practical work associated with feeding of the reindeer. We want to thank Andreas Pettersson for helping with the collection of the samples and Dr. Lars Johnsson for the help with organising of the feeding, slaughter and collection of the samples. We also wish to thank Johan Swahn, student at the department of Restaurant and Culinary Arts, Örebro University, for his skilful assistance in the sensory laboratory and Prof. Kerstin Lundström for the statistical expertise.