Use of natural phenols as feed supplements with antioxidant effects on poultry products

The oxidation of lipids is the main cause of nutritional and organoleptic deterioration of bird´s meat and eggs. This process originates compounds responsible for unpleasant odours, reduces the amount of polyunsaturated fatty acids, vitamins and pigments, decreases the acceptability on consumers and generates compounds that may present toxicity. Dietary supplementation is a simple strategy to include compounds in animal tissues. Synthetic antioxidants are regularly supplemented in poultry. However, recently, it has increased the search for replacing those compounds for others of a natural origin. This work evaluates the potential use of natural phenols (main components of essential oils) as diet supplement antioxidant agents. Firstly, we evaluated the effects of thymol and carvacrol on the delay of oxidative deterioration in domestic chicken muscle samples storage at 4°C for 0, 5 and 10 days, and in comparison with BHT (a synthetic antioxidant compound massively used). The results show that supplementation with the 3 compounds were equally effective to delay the lipid oxidation of peroneus longus samples with no significant effects on pectoralis major. Quail diet supplementation with thymol or isoeugenol did not show significant changes in meat samples, however, the oxidation levels of fresh egg-yolk samples were affected. Isoeugenol showed a yolk antioxidant effect of similar magnitude than BHT suggesting a protective effect of that phenol during the formation of the oocyte. Thymol showed intermediate effects. Results suggest that the level of lipid oxidation protection is dependent on the species and the type and age of the product. Secondly, we assess the effects of thymol and isoeugenol supplementation on liver and egg yolk fatty acid composition. Thymol increased total unsaturated liver fatty acids compared to isoeugenol, BHT and control samples. Isoeugenol increased palmitoleic acid in yolk samples compared to BHT and controls, with thymol showing intermediate results. Interestingly, BHT samples, showed a non expected increased in the saturated/unsaturated ratio. The results suggest the usefulness of natural phenols to delay lipid oxidation. The findings may be considered relevant from a human nutritional and avian biology point of view because phenol supplementation could affect reproductive and embryonic development.Fil: Marín, Raúl Héctor. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales; Argentina.Fil: Marín, Raúl Héctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Fil: Luna, Agustín. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales; Argentina.Fil: Luna, Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Fil Lábaque, María C. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales; Argentina.Fil: Lábaque, María C. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Fil: Zygadlo, Julio A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales; Argentina.Fil: Zygadlo, Julio A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina.Otras Ciencias Veterinaria

Thymol as natural antioxidant additive for poultry feed: oxidative stability improvement

Antioxidant are regularly included in poultry feed as protection from deterioration during storage. Recently the interest for the use of natural phytochemicals in animal diets has been increased. Thymol (THY) has been proven to be an effective antioxidant for extending broiler meat quality during storage with similar action to the widely used butylated hydroxytoluene (BHT). This study evaluates whether THY can also have a protective effect on the feed mash by assessing its antioxidant potential and related changes in fatty acid (FA) balance. Feed mash was assigned to 1 of 4 treatments, control (CON, no additive), vehicle (VEH, ethanol 96%), BHT (400 mg BHT /kg feed) and THY (400 mg THY /kg feed). Three replicates of each treatment were taken after 0, 30, and 60 d of storage at room temperature (23 ± 3◦C) and relative humidity (40 ± 5%). Peroxide value (PV), titratable acidity (TA) and FA relative composition were determined. As expected, there were no treatment effects on those variables at 0 d of storage. However, higher PV values were detected in the CON and VEH groups after 30 and 60 d of storage in comparison to the THY and BHT treated samples (CON = VEH > THY = BHT). While a slight increase was also observed in TA through storage time, no particular treatment effects were detected. Relative FA composition changed with storage time only in the CON and VEH group which had a decrease in polyunsaturated fatty acids and an increase in saturated FA. No changes were detected in the Thy and BHT treated feeds. The results suggest a similar THY and BHT protective effect on feed mash lipid oxidation. Thus, THY could be considered as a useful natural alternative to help sustain quality of poultry feed.Fil: Luna, Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Lema Alba, R. C.. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Dambolena, José Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Lábaque, María Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Marin, Raul Hector. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin