Aflatoxin B₁ (AFB₁) is classified as a hazardous mycotoxin, posing serious threats to public health and livestock production due to its detrimental effects on animal health and the integrity of the food supply chain. The Bacillus genus possesses strong adaptability, extensive enzyme secretion capabilities and probiotic characteristics, and demonstrates great potential in the degradation of mycotoxins. In the present study, we isolated a novel strain, Bacillus velezensis DZ013, from chicken feed, which exhibited significant activity in degrading aflatoxin B1. In vivo experiments demonstrated that dietary intervention of DZ013 significantly reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, enhanced hepatic catalase (CAT) and superoxide dismutase (SOD) activities, and decreased malondialdehyde (MDA) concentration in AFB₁-exposed broilers. Furthermore, DZ013 supplementation considerably alleviated hepatic histopathological damage and attenuated the inflammatory response through activation of the Nrf2 pathway and concurrently suppressed the NF-κB pathway. Collectively, our data reveal that DZ013 alleviates AFB1-triggered hepatic oxidative stress and injury by coordinately modulating the connection between the Nrf2 and NF-κB pathways, promoting antioxidant capacity while inhibiting inflammation, thereby providing a theoretical basis for bacterial biodetoxification and novel AFB₁ management strategies in poultry.

To Cite This Article: Yang H, Liu D, Liu F, Zhao L, Gao C, Liu S^`, Xing Z, Wu T, Pei X and Li D, 2026. Isolation of Bacillus velezensis DZ013 and its protective effects against aflatoxin b₁-induced hepatic oxidative stress and inflammatory injury in chickens. Pak Vet J, 2026, 46(10): 2601-2609. http://dx.doi.org/10.29261/pakvetj/2026.224