Transcriptome Response of Leukocytes from Chickens Infected with Avian Pathogenic Escherichia coli Identifies Pathways Associated with Resistance. Gallus gallus

Gene expression profiling of peripheral blood leukocytes in male broiler chickens exposed to APEC O1. Comparisons were made between Day 1 and Day 5 of all treatment groups, between differences in pathology and effect of vaccine on spleen gene expression. The goal was to determine expression differences that could convey genetic resistance to APEC O1. Overall design: Chickens were either challenged or non-challenged with APEC, vaccinated or non-vaccinated, with blood collected 1 or 5 days post challenge. The non-vaccinated, challenged group was further subdivided into mild and severe pathologay based on internal lesion scores. This created 10 groups, done in 4 replicates. The non-vaccinated, non-challenged, day 1 group was used as the reference for all other samples. Peripheral blood leukocytes were isolated from whole blood for analysis.