In a previous study, we examined the synergistic effects of the dietary supranutritional supplementation with vitamin E, vitamin C, and Se on the in vivo antioxidative status of broilers under conditions of dietary oxidative stress induced by feeding a diet high in n-3 PUFA. In this study, we examined the effect of their inclusion on the quality characteristics and oxidative stability of raw or cooked meat, both fresh or after a long-term frozen storage. Four hundred 21-day-old Ross 308 male broilers were allocated to 5 experimental groups fed 5% linseed oil-enriched finisher diets (days 21 to 40): Cont (recommended levels of vitamin E, C, and selenium), +E (200 IU vitamin E/kg feed), +C (250 mg vitamin C/kg feed), +Se (0.2 mg selenium/kg feed), or +ECSe (concentrations as in the sole supplementation, combined). Animal performance and carcass characteristics were monitored at the age of 40 D. Breast meat samples of 12 chickens per group were analysed fresh, fresh after frozen storage, cooked fresh, and cooked after frozen storage (2 × 2 factorial design) for parameters of meat quality (water-holding capacity—WHC, pH, and color) and oxidative stability (concentrations of vitamin E, malondialdehyde—MDA, antioxidant capacity of the water-soluble compounds—ACW, and fatty acid composition).Vitamin E alone (+E) and combined with Se and vitamin C (+ECSe) increased the α-tocopherol concentration in breast muscle, and showed similar protective effects against lipid peroxidation measured as MDA regardless of the frozen storage or cooking. The sole supplementation of vitamin C or selenium showed no effects on the meat quality parameters. In conclusion, the dietary supranutritional inclusion of vitamin E inhibited the lipid peroxidation in fresh, frozen stored, cooked fresh, and frozen stored meat in broilers fed with diets rich in n-3 PUFAs. Even though no clear synergistic effects of the supranutritional supplementation of vitamin C and Se with vitamin E were detected, their dietary inclusion did not negatively affect broilers carcass and meat quality parameters.

A trial was conducted to investigate whether, and if so to what extent, the combined supplementation of vitamin E, vitamin C, and selenium was superior to their sole supplementation concerning the oxidative stress induced by a high n-3 dietary polyunsaturated fatty acids (PUFA) intake in broilers. Four hundred 21-day-old Ross 308 male broilers were allocated to 5 experimental groups fed the following linseed oil (5%)-enriched finisher diets: Cont (no supplement), +E (200 IU vitamin E/kg feed), +C (250 mg vitamin C/kg feed), +Se (0.2 mg selenium/kg feed), or +ECSe (concentrations as in the sole supplementation, combined). Analyses of malondialdehyde (MDA), vitamin C, and α- and γ-tocopherols in plasma, antioxidant capacity of water- (ACW) and lipid- (ACL) soluble compounds in serum, and glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities in whole blood were performed. In breast muscle, analyses of MDA, α- and γ-tocopherols, ACW, selenium, and fatty acid (FA) composition were carried out. Birds fed the combination of antioxidants showed reduced average daily gain (ADG) and average daily feed intake (ADFI) and, as +E, lower MDA and γ-tocopherol, together with raised α- tocopherol levels in plasma and lower MDA and raised α- tocopherol levels in breast muscle compared to the control. The combination of antioxidants in the +ECSe group raised GPx activity in whole blood compared to the control. In conclusion, results indicated that vitamin E is the most effective antioxidant to alleviate oxidative stress caused by high dietary PUFA and that the supplementation with additional vitamin C and selenium did not have clear synergistic effect.

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Quality of poultry products, especially eggs, is a very important issue for the consumers and for the processing industry. The aim of the present study was to examine the interaction between the storage time and age of laying hens and their effect on the quality of table eggs. Eggs from 34 and 59- wk-old Bovans Brown hens were sampled and stored in the refrigerator for 1, 2, and 3 weeks. Significant effect of hen age (P<0.01) was found on egg weight, shell strength, albumen height and Haugh units (HU). Eggs from older hens had 2.58% higher mass compared to the eggs of young hens. Eggs from 59-weeks old hens had significantly lower shell strength (3.63 kg vs. 4.31 kg). Albumen height and HU were lower in eggs from the older hens compared to the young ones (5.7 mm vs. 7.11 mm for albumen height; 70.35 vs. 81.77 for HU). Significant negative effect of storage time was found on egg weight, albumen height, HU and yolk colour (P<0.01). The results indicated that egg quality characteristics monitored in this study decrease by hen age and during storage. The interaction effects between storage time and age of hens were significant only for yolk colour (P<0.05).

This study aimed to evaluate the long-term dietary effects of dried olive pulp (OP) on production performance, fatty acid profile and health lipid indices and quality characteristics of produced eggs, health and welfare indicators of laying hens. It was carried out in a commercial poultry farm using 300 Isa Brown layers at 23 weeks of age. The hens were randomly and equally divided in six dietary groups CON, OP2, OP3, OP4, OP5 and OP6, according to the inclusion rate of OP in the ration (0%, 2%, 3%, 4%, 5% and 6%, respectively). OP feeding increased the percentage of polyunsaturated fatty acids (PUFA) in eggs, decreased that of saturated fatty acids (SFA) and improved the PUFA to SFA ratio and health lipid indices, as indicated by the decrease of AI and TI and the increase in the h/H ratio of produced eggs, in a dose-dependent way. OP-fed layers presented a lower percentage of broken eggshells compared to controls. No adverse effects on birds’ performance, egg quality traits, health and welfare parameters were observed but a positive impact on Keel Bone Damage (KBD) incidence and belly plumage damage was recorded. OP feeding at the rates of 5% and 6% seems to be beneficial in improving egg nutrition quality.