Physical quality and antibacterial and antioxidant activities of egg albumen in laying hens fed a diet supplemented with turmeric powder

This study investigated the effects of dietary turmeric powder supplementation on egg physical quality and the antibacterial and antioxidant properties of egg albumen in laying hens. Seventy-five 43-week-old Lohmann Brown laying hens were randomly assigned to three dietary treatments in a completely randomized design: a basal diet (control), a basal diet supplemented with 0.25% turmeric powder (TP), and a basal diet supplemented with 0.50% TP. Each treatment consisted of five replicates of five hens and was administered for seven weeks. At the end of the trial, egg physical quality parameters were evaluated, while antibacterial activity against Escherichia coli, Salmonella typhimurium, and Staphylococcus aureus was determined using the agar well diffusion method. Antioxidant activity was assessed using the DPPH radical scavenging assay. Turmeric powder supplementation did not affect egg weight, egg index, albumen index, albumen weight percentage, or Haugh unit values (p > 0.05). However, antibacterial activity against E. coli increased significantly in the 0.25% and 0.50% TP groups compared with the control group (p = 0.004), whereas no effects were observed against S. typhimurium or S. aureus (p > 0.05). In addition, antioxidant activity increased dose-dependently from 25.5% in the control group to 32.9% and 38.8% in the 0.25% and 0.50% TP groups, respectively (p < 0.001). In conclusion, dietary supplementation with turmeric powder up to 0.50% enhanced the antibacterial activity of egg albumen against E. coli and improved its antioxidant capacity without affecting egg physical quality, highlighting its potential as a natural feed additive for producing eggs with enhanced functional properties.