Dietary supplementation of total flavonoids from Rhizoma Drynariae improves bone health in older caged laying hens

摘要

Caged layer osteoporosis (CLO) is a common bone metabolism diseases and poses a great threat to the production of laying hens. So far, there is no effective nutrition intervention to prevent CLO. The objective of this study was to evaluate the effects of dietary total flavonoids from Rhizoma Drynariae (TFRD), a Chinese herbal, on bone health, egg quality, and serum antioxidant capacity of caged laying hens. A total of two hundred sixteen, 54-wk-old Lohmann Pink-shell laying hens at were allocated to 3 groups with 6 replicates of 12 hens per replicate. The control group was fed a basal diet (BD) and 2 treatment groups additionally supplied with 0.5 or 2.0 g/kg TFRD, respectively. Results showed that supplying 2.0 g/kg TFRD enhanced the activities of serum total antioxidant capacity (P < 0.01) and glutathione peroxidase (P < 0.05) and had higher femur and tibia bone mineral density (both P < 0.05) compared with the control group. Dietary 2.0 g/kg TFRD also reduced the activities of serum alkaline phosphatase (P < 0.01), tartrate resistant acid phosphatase (P < 0.01), and the contents of osteocalcin (P < 0.01). Furthermore, tibia histomorphology observation showed that the microstructure of bone tissue was improved after TFRD treatment. Egg quality was not affected by TFRD while the egg weight significantly increased (P < 0.01). These findings suggested that TFRD has beneficial effects on bone health in older caged laying hens.