Fatty acid composition in maternal and foetal muscle tissues of beaver (Castor fiber)

The aim of the present work was to examine and compare the fatty acid composition of muscle tissues from eleven pregnant beaver (Castor fiber) females and their foetuses. The females were culled during warrantable early spring beaver hunting period (from the beginning of March until the middle of April). The fat content of the muscles of beaver female was 2.0 times higher (P < 0.001) than that of the muscles of their foetuses before birth. A total number of 33 and 34 fatty acids of various chain lengths and saturation levels, including 5 trans isomers, were identified, respectively, in the intramuscular fat (IMF) of muscle tissues from beaver females and their foetuses. Considerable differences in the proportions of individual fatty acids showed that foetuses during beaver gestation accumulate 1.4 times more total saturated (SFA) and 2.6 times more monounsaturated (MUFA) but 2.7 times less polyunsaturated (PUFA) fatty acids than pregnant females (P < 0.001). Although PUFA/SFA ratio in the tissues of foetuses was by 3.8 times lower (P < 0.001) than in the muscle tissue of females, the differences in n-6/n-3PUFA ratio were not significant (P = 0.133).