Dietary fat modulates dl-α-tocopheryl acetate (vitamin E) bioavailability in adult cockerels

Abstract

A trial was designed to assess the effect of fat supplementation (amount and type of fatty acids) on vitamin E bioavailability in adult cockerels.A total of 60 birds were force-fed three different diets: a semi-purified diet without added fat (Control diet) or supplemented with 3% fat as linseed (Linseed diet) or hydrogenated coconut oil (Coconut diet). The three experimental diets were also supplemented with dl-α-tocopheryl acetate to provide 40 mg vitamin E per bird.After one week of depletion, blood was collected from the wing vein before (baseline) and 6, 12, 24 and 96 h after the gavage. Plasma samples were analysed for their α-tocopherol, cholesterol and triglycerides concentrations.Results showed that the addition of 3% fat in the experimental diet increased post-gavage plasma α-tocopherol response by 153% for Linseed diet and by 75% for Coconut diet (P < 0.0001) compared to the Control group. Furthermore, the plasma α-tocopherol response observed with the Linseed diet was 44% greater than that observed with the Coconut diet (P < 0.0001). There was no effect of treatments on either plasma triglycerides (P = 0.91) or cholesterol (P = 0.45) responses.In conclusion, this study shows that the addition of 3% fat to the diet significantly increases dl-α-tocopheryl acetate bioavailability in adult cockerels. Supplementation of fat rich in unsaturated fatty acids also leads to a higher dl-α-tocopheryl acetate bioavailability than fat rich in saturated fatty acids.