Abstract: In order to study the role of chicken toll like receptor 4 playing in Salmonella infection, eighty three-day-old specific-pathogen-free chickens were randomly divided into 2 groups. The treatment group chickens were orally inoculated with 0.5 mL of the bacterial suspension containing 10⁸ CFU/mL Salmonella Serovar Pullorum. The control groups were inoculated with 0.5 mL saline. Eight chickens of each group were randomly chosen and killed at day 1, 3, 7 and 14 post infection. Spleen was sampled for RNA extraction. SYBR GreenⅠquantitative real-time PCR method was applied to compare the relative expression quantity of chicken TLR4 gene. The following results were obtained: TLR4 gene expression levels were significantly higher in chickens from treatment group than those in the control group at 4 time points (P<0.05), especially at day 3 and 7 post infection (P<0.01). These results indicated that the expression of chicken TLR4 gene was up-regulated during Salmonella infection.

Key words: chicken; TLR4 gene; Salmonella; real-time PCR