MBL2 and infection: Interestingly, in previous experiments the relative increase in serum MBL concentration elicited by ER infection of chickens [13] was the most prominent infection induced increase we have monitored in this species so far, approximately threefold higher than that observed after Escherichia coli infection [21] and twofold higher than that typically observed after infectious bronchitis virus (IBV) infection [22–24].