Maternal bile acids supplementation improves follicular development and offspring gut barrier by modulating Hedgehog-GnRH aixs and antioxidant pathways

With the extension of the egg-laying cycle, breeder hens experience ovarian oxidative stress and inflammation, resulting in ovarian dysfunction. This dysfunction triggers the decreasing of follicles number and increasing of follicular atresia, ultimately reducing egg production and quality, and potentially impairing offspring development. Bile acids (BAs), synthesized from cholesterol in the liver, are potent antioxidant and immunomodulatory molecules. This study aimed to investigate the effects of BAs supplementation on follicle and offspring development in breeder hens. A total of 192 Hy-Line Brown breeder hens were randomly assigned into 4 dietary treatments, with 8 replicates per treatment. The hens received diets with either normal protein (16.42%) or low protein (15.35%) levels, with or without BAs supplementation (120 mg/kg for 62-69 weeks, followed by 200 mg/kg for 70-75 weeks). We observed that BAs supplementation increased the number of pre-grade white and yellow follicles by promoting follicular development in breeding hens. Maternal nutrition with a low protein (LP) diet and BAs supplementation alleviated liver oxidative stress, enhanced intestinal immunity and promoted the intestinal development in offspring chicks. Therefore, a maternal LP diet with BAs supplement may serve as a nutritional strategy to improve the offspring growth and development of offspring.