Comparison of Fatty Acid Profile in Egg Yolk from Late-Age Hens Housed in Enriched Cages and in a Free Range System.

In recent years, the free-range system for laying hens has increased, driven by societal sensitivity to animal welfare. This study aimed to comparatively analyze the total lipid, cholesterol, and fatty acid composition of egg yolks of late-age laying hens reared in enriched cages (C) and the free-range system (FR). Eggs were collected from Lohmann Brown Classic hens at the 68th, 70th, 72nd, and 74th week of age. The concentrations of total lipids and cholesterol were not affected (p > 0.05) by either factor. Egg yolk from the FR group showed lower (p < 0.01) monounsaturated fatty acids and higher (p < 0.01) polyunsaturated fatty acid (PUFA) compared with that of the C group. From a nutritional point of view, the PUFA n-6/n-3 and the PUFA/SFA ratios of egg yolk from the FR group were favorably lower and higher (p < 0.01) compared with the C one. Conversely, hen age did not affect (p > 0.05) the fatty acid composition of yolks. Interactions between factors were found for total n-3 and n-6 PUFA and the n-6/n-3 ratio (p < 0.01), as well as the thrombogenic index (p < 0.05). In conclusion, the results confirmed that the free-range system may improve the nutritional yolk fatty acid profile and its positive impact on human health.

Qualidade de ovos comerciais submetidos a diferentes condições de armazenamento / Quality of commercial eggs submitted to different storage conditions

Verificou-se a qualidade interna de 1440 ovos de consumo, provenientes de galinhas de linhagem comercial. O delineamento foi inteiramente ao acaso, em arranjo fatorial 2x2x15, com duas diferentes idades das galinhas (33 e 60 semanas), duas condições de armazenamento (ambiente e refrigerado) e 15 períodos de estocagem (um, dois, três, quatro, cinco, seis, sete, oito, nove, 10, 11, 12, 13, 14 e 15 dias). Os parâmetros de qualidade dos ovos avaliados foram Unidades Haugh (UH), pH do albúmen (pH), sólidos totais do albúmen (STA) e da gema (STG), e peso e porcentagem de albúmen, gema e casca. Foi observada diminuição da qualidade interna dos ovos durante o armazenamento. Os ovos produzidos por poedeiras velhas e armazenados em temperatura ambiente apresentaram os piores resultados de UH. O pH do albúmen aumentou no decorrer do armazenamento independentemente da idade da ave e da temperatura de estocagem, e os valores de STA aumentaram com o armazenamento em temperatura ambiente. Concluiu-se que a idade da ave, a temperatura e o tempo de armazenamento dos ovos exercem influência sobre os parâmetros de qualidade do ovo.

Physical-chemical egg qualities of 1440 egg from commercial layer hens of different ages (30 and 60-week-old) submitted to storage under room temperature or refrigeration conditions were evaluated according to the following traits: Haugh Unities (UH); pH of albumen (pH); total solids of albumen and yolk; and weight and percentage of albumen, yolk, and shell. Decrease of inner quality of the evaluated eggs was observed during the experiment, mainly eggs from old-layers, which presented the worst values of AA and HU when stored at room temperature. It was concluded that age, temperature and time of storage of eggs influenced egg quality.