Effects of Pomegranate Peel Polyphenols on Egg Production and Health in Laying Hens

Background: Pomegranate peel polyphenols (PPPs) is a by-product of pomegranate. It has many biological activities, but it has not been used in laying hens. The effect of pomegranate peel polyphenols on laying hens is unclear. Methods: To understand the role of pomegranate peel polyphenols. We added different concentrations of pomegranate peel polyphenols to the diets of laying hens and studied the changes of growth performance, productivity performance and intestinal microbe during feeding. Result: The PPPs were found to reduce the feed-to-egg ratio in laying hens. Medium (MP, 500 mg) and high (HP, 750 mg) concentrations of PPPs increased the apparent digestibility of crude protein and calcium. Compared to the control group (CON), all egg performances in the MP group showed significantly improvement. There was a significant increase in reproductive hormones in the MP group compared with the low concentration (LP, 250 mg) and CON groups. As the concentration of PPPs increased, lg Y, SOD and CAT activity increased. The PPPs increased Thyroxine levels significantly. In the LP and MP groups, TNF-a and IL-6 levels were significantly lower than in the CON and HP groups. The relative abundance of Firmcutes increased with the rise in PPPs addition. While Bacteroidota decreased with increasing PPPs concentration. It was concluded that PPPs had a promoting effect on the growth performance for laying hens. This study found the best effects of PPPs addition at the medium concentration because high concentrations would have adverse effects on laying hens’ growth.