Serum levels of interleukin-6, alpha1-acid glycoprotein, and corticosterone in two-week-old chickens inoculated with Escherichia coli lipopolysaccharide

The concentration of interleukin-6 (IL-6), alpha1-acid glycoprotein (alpha1-AG), and corticosterone (CORT) was investigated chronologically (0 h to 14 d) in the sera of 2-wk-old specific-pathogen-free chicks inoculated with Escherichia coli lipopolysaccharide (LPS). In the LPS group the IL-6 level was elevated from 1 h to 2 d and was the highest at 3 h. From 4 to 14 d the IL-6 level was low in the LPS group. In the PBS group, IL-6 was not detected except a mild increase from 1 h to 6 h. In the LPS group, the alpha1-AG level increased from 6 h to 4 d, and the peak was 2 d. In the PBS group the alpha1-AG level was always low. The CORT level in the LPS group was higher than that of PBS group at 1 h. This study suggests that E. coli LPS may elevate serum IL-6 and CORT, and that IL-6 and CORT may increase the alpha1-AG level in the chicks.