Effects of hen genotype, age, and rearing system on egg quality in a sustainable perspective

Goalsofthe2030AgendaforSustainableDevelopmentincludesensuringsustainable consumption and production patterns. All countries are called for urgent actions to maximize the socio-economic benefits of the use of resources, while minimizing the climate, biodiversity and pollution impacts. Promotion of local chicken breeds is important to support biodiversity, contributing also to the environmental impact reduction through extensive rearing systems. The aim of this work was the quality assessment of eggs produced by two Italian local breeds (Bionda Piemontese, BP; Robusta Maculata, RM) and their crossbreeds with the hybrid Sasso (BPxS and RMxS); eggs laid by Lohmann Brown (L) were considered as the reference. All the hens were reared in enriched cages and free-range systems (3 replicates for each system/genotype; 10 birds in each replicate).At the hen age of 26, 49, and 65 weeks, the eggs (20 for each replicate) were collected and analysed for quality attributes, including nutritional properties. The multivariate elaboration of analytical results gave a robust assessment of egg qualitydepending on hen genotype, age, and rearing systems. Differences in egg nutritional properties were small and not relevant from a human perspective. The most important factor for techno-functionality resulted the hen age: eggs laid by older hens were heavier, with higher yolk percentage, and better foaming properties. Crossbreeds increased egg weight and breaking strain. BP, RM, and their crossbreeds gave gelling properties better than L, which, in contrast, showed higher foaming capacity. Egg yolk and foam consistency resulted increased in the eggs from free-range system.