Effects of bacteriophage supplementation on performance, gut health and blood biochemistry in broilers challenged with necrotic enteritis.

Necrotic enteritis (NE), primarily caused by Clostridium perfringens (CP) type G, poses a significant threat to broiler health and performance, especially in antibiotic-restricted production systems. Bacteriophage therapy is emerging as a promising alternative to antibiotics for controlling enteric pathogens in poultry, including CP. However, a critical knowledge gap exists in specifically determining the in vivo effects of bacteriophages combined with probiotics against CP strains associated with NE in broilers under practical conditions. Therefore, this study aimed to evaluate the efficacy of a bacteriophage preparation (PathoGone™-DWA; containing Bacillus subtilis + Phages cocktail) administered via drinking water in NE-challenged broilers. In total, 576 one-day-old (Ross-308) male chicks were randomly assigned to four treatments (6 pens of 24 birds): (1) Negative Control (NC; uninfected + basal diet), (2) Positive Control (PC; infected + basal diet), (3) Low Dose Bacteriophage (LD-BP; infected +0.6 g/pen/day), and (4) High Dose Bacteriophage (HD-BP; infected +1.2 g/pen/day). Birds were orally predisposed with 10× coccidia vaccine (1 mL/bird) on day 15, followed by oral inoculation with a pathogenic (NetB-positive) field strain of C. perfringens type G (1 mL; 1 × 10 CFU/mL/ bird) on day 19 and 20. Bacteriophage supplementation significantly improved feed intake, body weight gain, and feed conversion ratio (P < 0.05), while reducing intestinal lesion scores and mortality. Jejunal histomorphology and hematological indices depicted a notable restoration (P < 0.05) of NE-associated gut damage and blood abnormalities. Serum biochemistry also showed marked improvement (P < 0.05) in protein, glucose, lipid profile, liver enzymes, and renal markers. In conclusion, bacteriophage supplementation (PathoGone™-DWA) significantly improved performance metrics, mitigated intestinal damage, and restored hematological and biochemical disturbances in broilers challenged with NetB-positive CP, highlighting its efficacy as a targeted, antibiotic-free intervention against NE.