Abstract. The aim of this study was to determine the effect of vitamin E and
polyphenols on the antioxidant potential and meat quality of broiler chickens
fed diets supplemented with low-quality oil. The experimental materials
comprised 120 male Ross 308 broilers (six treatments, 10 replications, two
birds per replication). Dietary supplementation with vitamin E and/or
polyphenols was applied in the following experimental design: group I
(negative control) – without supplementation without low-quality oil; group
II (positive control) – without supplementation + low-quality oil; group
III – supplementation with 100 mg kg−1 of vitamin E+ low-quality
oil; group IV – 200 mg kg−1 of vitamin E + low-quality oil; group V
– 100 mg kg−1 of vitamin E and 100 mg kg−1 of polyphenols +
low-quality oil; group VI – 200 mg kg−1 of polyphenols +
low-quality oil. Rapeseed oil oxidised under laboratory conditions was added
to the diets of broiler chickens from groups II to VI. The applied
antioxidants had no effect on the growth performance of chickens fed oxidised
oil. Increased dietary inclusion levels of vitamin E and/or polyphenols
improved the antioxidant status in the blood and increased the content of
non-enzymatic antioxidants in the liver and breast muscles of broilers fed
low-quality oil. The tested antioxidants had no influence on carcass quality
parameters in chickens fed oxidised oil. However, birds fed diets with the
addition of vitamin E were characterised by a higher gizzard weight and
higher pH of gizzard digesta. Dietary supplementation with vitamin E and
polyphenols or polyphenols alone contributed to a lighter colour and lower pH
of breast muscles and an increase in the content of fat and ash in the breast
muscles of broilers fed oxidised oil. The breast muscles of birds given 100
or 200 mg kg−1 of supplemental vitamin E were characterised by higher
concentrations of n-6 polyunsaturated fatty acids (PUFAs) and
hypocholesterolemic fatty acids (DFAs), a more desirable DFA∕OFA
ratio, and a lower
atherogenicity index (AI). Polyphenols combined with vitamin E can be a
valuable component of diets for broiler chickens when the problem of
low-quality oil occurs.
Grape pomace improves performance, antioxidant status, fecal microbiota and meat quality of piglets
