The effect of feeding rosemary, oregano, saffron and &#945-tocopheryl acetate on hen performance and oxidative stability of eggs

In this study the effects of feeding rosemary, oregano, saffron and α-tocopheryl acetate on hen performance and egg quality were investigated. One hundred-twenty Lohmann laying hens, 32 weeks old, were divided into five groups replicated four times with six hens per replicate. One group was given a basal diet and served as control (CON). The experimental diets given to the other four groups were based on the basal diet but contained an additional 200 mg α-tocopheryl acetate/kg (TOC), or rosemary at 5 g/kg diet (ROS), oregano at 5 g/kg diet (ORE) or saffron at 20 mg/kg diet (SAF). At the end of the feeding trial that lasted 56 days, hen performance and some egg quality characteristics were determined, whereas the oxidative stability of the refrigerated stored shell eggs and liquid yolks were also examined. Results showed no significant differences in egg production, feed intake, feed conversion ratio, egg weight and shape, yolk shape, Haugh units and shell thickness among treatments. However, yolk colour was significantly improved in the SAF group compared to all other groups. The extent of lipid oxidation in shell eggs differed among the dietary treatments, but did not change with storage time. In liquid yolk at pH 6.2, lipid oxidation was higher in the CON group compared to all other groups. The ORE group presented lower oxidation rate than the ROS group, but higher than the SAF group, which in turn exhibited higher oxidation rate than the TOC group. When liquid yolk was acidified to pH 4.2, the lipid oxidation profile remained unchanged but the rate was much more intense. Keywords: Rosemary; oregano; saffron; α-tocopherol acetate;egg quality; hen performance; oxidative stability South African Journal of Animal Sciences Vol. 35 (3) 2005: pp.143-15

The effect of a mixture of herbal essential oils or á-tocopheryl acetate on performance parameters and oxidation of body lipid in broilers

No Abstract. South African Journal of Animal Science Vol. 34 (1) 2004: pp.52-6

Extratos etanólicos de manga como antioxidantes na alimentação de poedeiras

O objetivo deste trabalho foi avaliar o efeito de extratos etanólicos do caroço e da casca de manga, sobre o desempenho de poedeiras e sobre a qualidade e estabilidade lipídica dos ovos. Um total de 180 poedeiras comerciais Hisex White foi distribuído ao acaso em seis tratamentos, com cinco repetições de seis aves. Os tratamentos consistiram de: ração sem adição de antioxidante; ração com 200 ppm do antioxidante butilato de hidroxitolueno (BHT); ração com 200 ou 400 ppm de extrato da casca de manga (Ecas); ração com 200 ou 400 ppm de extrato de caroço de manga (Ecar). Foram avaliados: o consumo de ração, a produção de ovos, o peso do ovo, a massa de ovo produzida (grama por ave por dia), a conversão alimentar e características de qualidade dos ovos. A oxidação lipídica da gema durante o armazenamento foi determinada pela quantificação das substâncias reativas ao ácido tiobarbitúrico. As aves alimentadas com a ração sem adição de antioxidantes produziram ovos com os piores valores de unidade Haugh e maior oxidação lipídica da gema. Os teores de 400 ppm de Ecas e 200 ou 400 ppm de Ecar foram efetivos na prevenção de danos oxidativos aos ovos durante o armazenamento e podem ser utilizados na alimentação das poedeiras como substituto ao antioxidante sintético