Dietary apidaecin supplementation improves intestinal health in laying hens and reduces egg Salmonella load

This study evaluated the impact of apidaecin on the production performance and intestinal health of laying hens. A total of 288 45-wk-old Hy-Line grey laying hens were randomly assigned into 4 groups with 6 replicates of 12 birds each. The Con, Api300, Api500 and Api700 groups were fed the basic diet supplemented with 0, 300, 500 and 700 mg/kg apidaecin respectively for 12 weeks. Results indicated that daily feed intake, crypt depth and V/C of intestinal tract were quadratic functions with apidaecin supplementation (P < 0.05). Apidaecin modulated gut microflora by increasing beneficial bacteria that produced SCFAs such as Phascolarctobacterium and Odoribacter, and decreasing pernicious bacteria that produced toxins such as Actinobacillus (P < 0.05). These beneficial effects were maximized at 500 mg/kg of apidaecin addition.