Fatty acid composition of depot fats from gnotobiotic lambs

Abstract

SUMMARYThe fatty acid composition of the depot fats of lambs reared for 4–5 months under gnotobiotio conditions have been determined and an estimate made of the endogenous synthesis of stearic acid.In an uninoculated gnotobiotic lamb no hydrogenation of dietary lipids occurred in the rumen and this was reflected in the virtual absence oftransacids in depot lipids. In this animal the stearic acid content of perirenal depot fat accounted for 16% of the total fatty acids which was similar to the value found in newborn lambs (17%). Inoculation of the rumen of two gnotobiotic lambs with seven species of bacteria resulted in the establishment of partial hydrogenation processes in the rumen. Varioustransisomers of octadecenoic acids were produced in these lambs from the dietary fatty acids but no stearic acid was formed.These findings are compared with the fatty acid composition of depot fats of other herbivorous and omnivorous animals.