Influence of housing system and feeding on some egg qualitative characteristics

In the present paper are shown the results of a trial concerning the influence of housing system (outdoor vs battery cages) and feeding (conventional vs. organic diets) on some egg qualitative characteristics. During a five month-period, four groups of 27 Hy-Line (8.5-9-month-old) laying hens were studied: AT (in which hens were kept outdoor and fed a conventional diet); AB (in which hens were kept outdoor and fed an organic diet); GT (in which hens were kept into battery-cages and fed a conventional diet) and GB (in which hens were kept into battery-cages and fed an organic diet). Freshly laid eggs were collected at the beginning of the trial and every three weeks up to the end of the trial to determine some physical and qualitative parameters. The experimental conditions did not affect the bird’s health and mortality rate was very low. Feed intake and conversion index of group AT +AB were, on the whole, higher than those of group GT+GB. During the trial, the higher percentage of yolk and of the eggshell was detected in eggs of group AT+AB. Haugh index and pH values were often improved in eggs deriving from hens allocated in cages. Yolk from groups AT and AB was more intensively coloured, owing to the possibility to eat feeds containing xanthophylls, such as grass, herbs and insects. The comparison between the types of diets (conventional vs organic) did not pointed out any significant difference.We can conclude that some egg quality characteristics can be significantly influenced by the housing system. ,