Fig. 1.

Relative TLR3 and TLR7 mRNA expression in trachea and lungs of chickens infected with the Conn A5968 strain of IBV. (A) and (B) represent relative TLR3 and TLR7 mRNA expression in trachea, respectively. (C) and (D) represent TLR3 and TLR7 mRNA expression in the lung, respectively. Chickens were infected intra-tracheally with the Conn A5968 strain of IBV at 6 days of age and trachea and lung tissues were collected at 12, 24, 48, and 72 h post-infection (hpi). There were five IBV-infected chickens at each time point (six animals were sampled at 12 hpi) and five PBS-treated chickens used as controls for each time point (only two animals were sampled at 72 hpi for the control group). Target mRNA expression was normalized via the geometrical mean of Eff.(uninfected control)^Cp for all control genes (β-actin and ubiquitin). Error bars represent standard error of the mean (SEM). ⁎=relative mRNA expression is significantly up-regulated when compared to the uninfected controls and ⁎⁎=relative mRNA expression is significantly down-regulated when compared to controls.