Dietary hawthorn-leaves flavonoids improves ovarian function and liver lipid metabolism in aged breeder hens

Hawthorn-leaves flavonoids (HF), extracted from hawthorn leaves, were reported to exert antioxidant, anti-inflammatory and hypolipidemic properties. The aim of our study was to investigate the effects of dietary HF on the reproduction performance and liver lipid metabolism of aged breeder hens. A total of 270 aged Qiling breeder hens (60-wk-old) were randomly divided into 3 treatments: 1) basic corn-soybean diet (CON); 2) basic corn-soybean diet supplemented with 30 mg/kg HF (LHF); 3) basic corn-soybean diet supplemented with 60 mg/kg HF (HHF). The results showed that supplemented HF significantly improved the egg-laying rate and hatching rate of aged breeder hens (P < 0.05). HF treatment reduced the serum TG, T-CHO and L-LDL levels (P < 0.05), and upregulated the mRNA expressions of ESR1, ESR2, VTGⅡ, ApoB, and ApoVI in the liver (P < 0.05). Serum estrogen levels in HF treated groups were elevated compared with the CON group (P < 0.05). In the HHF group, the number of the primordial follicles was higher in comparison with the CON group (P < 0.05). Furthermore, dietary supplementation with HF improved the activity of antioxidant enzymes (T-AOC, GSH-Pχ) (P < 0.05), following with the reversed ovarian apoptosis and morphological damage. In addition, 60 mg/kg dietary HF upregulated the protein expression of PCNA and Nrf2 in the ovary (P < 0.05). In summary, dietary supplementation with HF could improve the reproduction performance through regulating liver lipid metabolism and improving ovarian function in aged breeder hens.