Free Dietary Choice and Free-Range Rearing Improve the Product Quality, Gait Score, and Microbial Richness of Chickens

SIMPLE SUMMARY: The worldwide demand for productivity and quality meat, eggs, and other animal products is increasing. More and more people are expressing concerns relating to product quality and animal welfare. Our study aimed to provide scientific knowledge regarding how welfare factors contribute to quantity and quality of chicken. We used 400 Beijing You chickens to compare welfare factors by providing free dietary choice under cage rearing, and further comparing cage rearing with the free-range rearing system. Results showed that under cage rearing, free dietary choice of mealworms and fresh grass contributed to better meat quality, gait score and foot pad dermatitis than the conventional cage feeding and rearing system. This also gave rise to higher values of blood platelets and a richer gut microbial composition. As compared to caged chickens, free-range chickens developed better meat quality, gait score, and feather conditions, as well as a richer microbial composition. Our work provides a comprehensive understanding of welfare factors under both cage and free-range systems, and also broadens knowledge of health-related gut microbial composition in chickens. ABSTRACT: Poultry welfare has been extensively studied; however, there is a lack of rigorous scientific knowledge relating to the different aspects of welfare factors and how this may contribute to the production quantity and product quality as well as the welfare of chickens. Therefore, we conducted an integrated study to compare welfare factors in chickens by providing free dietary choice under cage rearing, and further comparing cage rearing with free-range rearing. One hundred chickens each were allocated to a cage rearing group with conventional feeding (CC), a cage rearing group with free dietary choice of mealworms (FDM), a cage rearing group with free dietary choice of mealworms and fresh grass (FDMG), and a free-range rearing system group with free dietary choice of mealworms and fresh grass (FRMG). Results showed that under cage rearing, free dietary choice contributed to better meat quality and gait score, higher values of blood platelets, and a richer gut microbial composition, but poorer egg production than CC chickens. As compared to FDMG, FRMG chickens showed better meat quality, gait score, and feather conditions, as well as a richer gut microbial composition; however, they had poorer egg production and a poorer foot pad and foot feather condition. We conclude that free dietary choice and free-range rearing systems improve the product quality, gait score, and microbial richness of chickens.