Antioxidant yeast culture mitigates aflatoxin B1-induced liver injury in broiler ducks and its underlying mechanism.

Aflatoxin B1 (AFB1) in feed poses a serious threat to animal health and production performance. Oxidative damage is one of the key mechanisms by which AFB1 exerts its toxicity.Antioxidant yeast culture (AYC) is a potential dietary additive with hepatoprotective and antioxidative properties. This study aimed to evaluate the protective role of AYC against AFB1-induced liver injury and impaired growth performance in broiler ducks. A total of 240 one-day-old Cherry Valley ducks were randomly assigned to five treatments varying AFB1(0, 1 mg/kg) and AYC dose(0, 2.5, 5 %). Dietary AFB1 exposure significantly reduced average daily gain (ADG), and mortality both at day 14 and 35, while AFB1 reduced average daily feed intake (ADFI) and increased ratio of feed and gain at day 14. AEB1 exerted liver damage, evidenced by increased liver indices, serum biochemical parameters, oxidative stress and inflammatory response, accompanied by histological changes, including hemorrhage, bile epithelial hyperplasia and vaculation. AFB1 upregulated IL-18, Caspase-1, and IL-1β expression, while downregulating PI3K, Akt, and glycogen synthase kinase 3β (GSK-3β) mRNA, while the inhibition of the PI3K/Akt pathway by AFB1 resulting in caspase-1-mediated pyroptosis, leading to inflammation and liver injury. Supplementation with 5.0 % AYC scavenged excess reactive oxygen species (ROS) generated by AFB1. This in turn promoted the expression of the PI3K/Akt pathway and inhibited the production of factors associated with pyroptosis, and reversed the performance loss and liver injury caused by AFB1.These findings brings insights into the mechanism underlying AFB1 hepatotoxicity and demonstrate the potential for applying AYC to mitigate AFB1 exposure in poultry.