Simple Summary
Late-phase laying hens frequently experience oxidative damage and impaired intestinal health, lowering egg quality and causing economic losses for poultry farmers. The present work set out to characterize how basal diets supplemented with Pieris japonica leaf powder (PJP) alter egg-related measurements, hepatic antioxidant status, duodenal histomorphology, and cecal microbial profiles of layers. Over a 10-week animal feeding assay, 56-week-old commercial layers were allocated to four dietary groups receiving graded inclusion rates of PJP. Moderate PJP supplementation increased eggshell thickness, enhanced hepatic antioxidant capacity, improved duodenal mucosal morphology, and reshaped cecal bacterial communities. High-dose PJP exerted adverse effects on egg-related indices. Among the tested dosages, the 0.10% inclusion level produced the most favorable comprehensive outcomes. This plant powder exhibits potential for development as a plant-derived feed additive candidate, while its feeding safety still requires further validation before practical application in commercial egg-production farms.
Abstract
Oxidative stress and intestinal health are critical factors that are closely linked to the production performance and physiological status of laying hens. This work assessed how dietary incorporation of Pieris japonica leaf powder (PJP) shapes egg quality attributes, hepatic antioxidant defence, gut tissue morphology, and cecal microbial community profiles in layers. A total of 360 healthy 56-week-old Hy-Line Brown layers were randomly assigned to four treatments, each containing six replicate pens housing 15 birds apiece. Animals received basal feeds containing 0.00% (control), 0.05%, 0.10%, or 0.20% PJP throughout the 10-week experimental run that including a 2-week adaptation period. Relative to the control group, diets with 0.05% PJP significantly increased eggshell thickness (p < 0.05). Hepatic total antioxidant capacity (T-AOC), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were significantly elevated in PJP-supplemented groups (p < 0.05). The 0.10% PJP addition improved duodenal villus-height-to-crypt-depth ratio (V/C). Regarding cecal microbiota, 0.10% PJP reduced the Simpson index while elevating Collinsella relative abundance (p < 0.05). Noticeably, the 0.20% supplementation exerted adverse effects on egg-related indices. Correlation analysis indicated that cecal microbiota was closely associated with hepatic antioxidant indices and eggshell-related indicators. In summary, dietary PJP inclusion may improve the eggshell thickness of eggs from laying hens by enhancing host antioxidant defense, reshaping the composition of cecal microbial communities. It was reported that 0.10% PJP supplementation yielded the most favorable comprehensive responses under the conditions adopted within this trial.