Abstract
The hypothesis tested was that the feeding of n-6 polyunsaturated fatty acids (n-6 PUFA) instead of Saturated Fatty Acids (SFA) results in more whole body fatty acid oxidation associated with enhanced whole body energy expenditure. To put the hypothesis to the test, broiler chickens were fed diets containing either beef tallow as source of SFA or a sunflower-oil blend as source of n-6 PUFA. Seven days old, male broiler chickens were used, they were kept individually in cages from 1-4 weeks of age. The experimental diets did not significantly affect growth performance. In broilers fed, the diet rich in n-6 PUPA, the ratio of deposition in the body to intake of digestible total PUPA which reflected n-6 PUPA was significantly decreased, pointing at preferentially increased n-6 PUFA oxidation The ratio for n-9 Monounsaturated Fatty Acids (MUFA) was >1.0 which agrees with net de-novo synthesis but there was no diet effect. Feeding either the diet rich in n-6 PUFA or SFA did not influence energy expenditure. This study supports the idea that dietary n-6 PUPA instead of SFA are preferentially oxidized but no proof was obtained for enhanced energy expenditure.