Effects of different levels of dietary supplemental caprylic acid and vitamin E on performance, breast muscle vitamin E and A, and oxidative stability in broilers

Abstract

The paper reports data from four experiments (EXP). Broiler cockerels Ross 308 were allocated to 3 or 5 (EXP 4) dietary treatments comprising 300 (3 replicated pens of 100 chicks per pen), 50, 50 or 100 chickens. The EXP lasted 42, 38, 42 and 38 days. All basal diets contained adequate ingredients. The inclusion of 0.5% caprylic acid (CA) in diets reduced (<I>P </I>< 0.05) body weight (EXP 1). The results of EXP 3 and 4 indicated that the diet supplemented with 0.25% CA and 30 mg vitamin E (total vitamin E concentration 50 mg) resulted in similar BW like the basal diet, but the increased supplemental vitamin E to 150 mg (EXP 3) or to 100 mg (EXP 4) decreased (<I>P </I>< 0.05 and <I>P </I>< 0.001) BW and increased mortality. No differences were found between the fat and crude protein contents in dry matter of breast meat. Higher vitamin E doses in feed mixture significantly (<I>P </I>< 0.001) increased the content of vitamins soluble in fats in breast meat – vitamin E (from 28.54 in the control to 80.28 mg/kg of dry matter) and vitamin A (from 0.34 to 0.44 mg/kg of dry matter). The addition of caprylic acid significantly decreased the speed of lipid oxidation measured after 3 (<I>P </I>< 0.02) and 5 (<I>P </I>< 0.05) days of storage in refrigerator at a temperature from 2.5 to 4°C. On the contrary, higher vitamin E doses and basal diet without CA supplement increased the oxidation of lipids.