||Laying hens are kept in different systems, and the first number of the egg code defines through which system has been produced: battery cage (nº3), barn (nº2), free range (nº1) and organic (nº0). Hens kept in cages are in a higher density and have higher egg production, probably due to a more effective egg collection (Flock. 2008. Lohmann Information. 43:13-21). In addition, this system has the advantage of having lower production costs. It is assumed that the alternative systems (barn, free range and organic) provide more welfare for the hens, but some studies show higher mortality in them (Burch. 2012. Vet Rec. 171:649-50). The consumption of eggs in Catalonia has been reduced in recent years and its price has been increased following the ban on non-enriched cages. Only a low percentage of consumers in Catalonia can identify the egg code.