Evaluation of Physical Egg Quality Parameters of Commercial Brown Laying Hens Housed in Five Production Systems

SIMPLE SUMMARY: Avian welfare has become a highly debated issue for many activist groups and legislators over the past several years. Recently, the EU and several US states have banned the use of traditional cage environments. Therefore, it is important for producers and researchers to understand how this shift toward extensive environments will affect the quality of eggs being produced. The objective of this study was to identify how the five most used environments (cages, barren colony cages, enriched colony cages, cage-free, and free-range) affects the egg quality of brown egg layers (shell color, Haugh unit, yolk color, vitelline membrane, and shell strength). This study found that free-range eggs had superior egg quality parameters while, in most cases, eggs from both colony cages had inferior quality parameters. It was also found that both barren and enriched colony cages were not different in production parameters, indicating that simply adding enrichments to a cage environment will not change egg quality. This information shows that, as the egg industry moves toward greater adoption of extensive environments, egg quality will improve for brown egg layers, possibly allowing some of the costs to be offset. ABSTRACT: This study evaluates the effect of housing environment on the egg quality characteristics of brown egg layers as many different environments are currently used in the industry. Battery cages, barren colony cages, enriched colony cages, cage-free, and free-range environments were evaluated. Overall, all egg quality measurements were affected by housing environment (p < 0.01) except for vitelline membrane strength, elasticity, and egg solids. Eggshells and yolks were lightest in barren colony cages and darkest from free-range hens (p < 0.0001). Free-range eggs were heavier than eggs from all other environments (p < 0.0001). Cage-free eggs had lower albumen height and Haugh units than other environments (p < 0.0001). Lastly, cage-free and free-range eggs had stronger eggshells than the other environments (p < 0.0001), and free-range eggs had more elastic eggshells than eggs from conventional battery cages and barren colony cages (p < 0.01). Access to the range seemed to give free-range hens different nutritional advantages, which allowed for the darker yolks and shells. Furthermore, eggs from barren colony cages seemed to exhibit more negative characteristics. Simply adding enrichments to colony cages did not improve or detract from egg quality. From this research, it appears that, as the industry moves toward extensive environments, the egg quality of brown egg layers will improve.