Detection and investigation of Escherichia coli in contents of duodenum, jejunum, ileum and cecum of broilers at different ages by PCR

Escherichia coli strains cause a number of diseases in broiler chickens, ultimately leading to death or to a decrease in production or the condemning of carcasses. In this study, the isolation and molecular detection of E. coli from broiler chicken gut contents is described. Broilers were raised under conditions identical to those found in commercial broiler operations. At 4, 14 and 30 days of age, twenty four birds were randomly sacrificed and contents of duodenum, jejunum, ileum and cecum were removed. After DNA extraction, these samples were subjected to an optimized PCR to detect the presence of E. coli and to determine its presence or absence in intestinal segment contents at different ages. For all gut segments, a total of 43.7, 21.8 and 37.5% of samples were positive for E. coli by PCR at 4, 14 and 30 days, respectively. A total of 87.5, 25 and 87.5% cecum samples were positive for E. coli by PCR at 4, 14 and 30 days, respectively. Posterior segments exhibited lower levels of E. coli compared with the anterior segments, especially the cecum. Furthermore the PCR protocol used in this work was shown to be an efficient method to detect E. coli in naturally contaminated intestinal samples, as accurate and certainly quicker than culture and other detection methods.