The aim of this study was to investigate the protective effects of selenium yeast (Se-Y) against hepatotoxicity induced by ochratoxin A (OTA). The OTA-induced liver injury model was established in chickens by daily oral gavage of 50 µg/kg OTA for 21 days. Serum biochemistry analysis, antioxidant analysis, as well as the qRT-PCR and Western blot (WB) analyses were then used to evaluate oxidative damage and apoptosis in chicken liver tissue. The results showed that Se-Y significantly increased liver coefficient induced by OTA (P < 0.05). OTA + Se-Y treated group revealed that Se-Y reduced the OTA-induced increase in glutamic pyruvic transaminase (ALT), glutamic oxaloacetic transaminase (AST) and malonaldehyde (MDA) content, and reversed the decrease in antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) (P < 0.05). In this study, we found that OTA is involved in the mRNA expression levels about Nrf2/Keap1 and PI3K/AKT signaling pathways, such as oxidative stress-related genes (Nrf2, GSH-Px, GLRX2 and Keap1) and apoptosis-related genes (Bax, Caspase3, P53, AKT, PI3K and Bcl-2). Besides, significant downregulations of protein expression of HO-1, MnSOD, Nrf2 and Bcl-2, as well as a significant upregulation of Caspase3 and Bax levels were observed after contaminated with OTA (P < 0.05). Notably, OTA-induced apoptosis and oxidative damage in the liver of chickens were reverted back to normal level in the OTA + Se-Y group. Our findings indicate that pretreatment with Se-Y effectively ameliorates OTA-induced hepatotoxicity.

Chicken anemia virus (CAV) targets the immune system of chickens, causing anemia and atrophy of the bone marrow and lymphoid organs, resulting in significant damage to poultry farming. From April 2024 to March 2025, a total of 359 liver samples were collected from broiler farms in 11 cities across Liaoning Province. CAV was detected using PCR, and 16 complete genome sequences of CAV isolates from different regions were analyzed through phylogenetic and recombination analyses. The overall CAV positivity rate was 13.9%, with spring identified as the peak season. Phylogenetic analysis and genotyping revealed that ten CAV strains clustered within subgroup C1, while the remaining six were distributed among subgroups C2 and C3, as well as Group D. Specific mutations were observed among the VP1 protein genotypes, including mutations previously associated with increased pathogenicity and transmission. One isolate, LN2511, was identified as a potential recombinant strain with its parents CAV-Shanxi7 and CAV-EG-13. During 2024–2025, CAV infection remained prevalent in Liaoning Province, with subtype C1 being the dominant genotype. Amino acid sequence analysis indicated the presence of highly pathogenic strains across the province. These findings fill a knowledge gap regarding CAV infection status and evolutionary trends in chicken populations in Liaoning, China.