Effect of housing system and age on products and bone properties of Taihang chickens

The aim of this study was to compare egg quality, carcass, meat characteristics, and bone properties of Taihang chickens in 2 different housing systems at various ages. A total of 168 birds were selected and randomly allocated to 2 groups at 23 wks and raised in conventional cage (CC) or flattening on floor (FF) housing system, respectively. FF hens' egg weight, albumen height, and Haugh unit were higher (P < 0.05), and yolk weight was lower (P < 0.001) than those of the CC hens. Egg quantity of FF hens was higher than that of the CC hens (P < 0.01). The FF hens' weight (P < 0.05) and breast meat percent (P < 0.01) were higher than those of the CC hens. The highest live body and carcass weight were observed at 57 wk (both P < 0.01), whereas the highest semieviscerated percentage (P < 0.01) and meat weight of breast and thigh (P < 0.05) were shown at 49 wk. The highest eviscerated percentage and thigh meat were displayed at 41 and 32 wk, respectively (P < 0.01). For meat color, the lightness of both breast and thigh meat in the FF group was significantly reduced compared with those of the CC group (P < 0.01 and P < 0.05). FF hens' humerus weight and breaking strength (both P < 0.01) and tibia breaking strength (P < 0.05) were significantly higher than those of the CC hens. Femur breaking strength was significantly affected by hens' age (P < 0.01). Egg weight, albumen height, Haugh unit, yolk color (all P < 0.01), pH of thigh meat, semieviscerated, and eviscerated weight (all P < 0.05) were influenced by the interaction of housing system and age, whereas no change in moisture loss rate, meat color, shearing force, and bone quality was found (P > 0.05). In summary, in the 2 housing systems, hens' age and their interaction could affect slaughter performance, quality of egg, meat, and bone of Taihang chickens. In addition, the results of the present study support a theoretical basis for the development and utilization of Taihang chickens in accordance with the FF system.