Postbiotic, anti-inflammatory, and immunomodulatory effects of aqueous microbial lysozyme in broiler chickens

Lysozymes, efficient alternative supplements to antibiotics, have several benefits in poultry production. In the present study, 120, one-day-old, Ross 308 broiler chickens of mixed sex, were allocated into 2 equal groups, lysozyme treated group (LTG) and lysozyme free group (LFG), to evaluate the efficacy of lysozyme (Lysonir^®) usage via both drinking water (thrice) and spray (once). LTG had better (<i>p</i> = 0.042) FCR, and higher European production efficiency factor compared to LFG (<i>p</i> = 0.042). The intestinal integrity score of LTG was decreased (<i>p</i> = 0.242) compared to that of LFG; 0.2 vs. 0.7. Higher (<i>p</i> ≤ 0.001) intestinal Lactobacillus counts were detected in chickens of LTG. Decreased (<i>p</i> ≤ 0.001) IL-1β and CXCL8 values were reported in LTG. The cellular immune modulation showed higher (<i>p</i> ≤ 0.001) opsonic activity (MΦ and phagocytic index) in LTG vs. LFG at 25 and 35 days. Also, higher (<i>p</i> ≤ 0.001) local, IgA, and humoral, HI titers, for both Newcastle, and avian influenza H5 viruses were found in LTG compared to LFG. In conclusion, microbial lysozyme could improve feed efficiency, intestinal integrity, <i>Lactobacillus</i> counts, anti-inflammatory, and immune responses in broiler chickens.