Purpose: To investigate the prevalence of E. fergusonii in broiler chicken farms located in the Fraser Valley of British Columbia, and to develop a simple and accurate molecular identification method of this bacterium.
Methods: Five hundred eighty broiler chickens aged from 28 to 36 days were sampled from 32 farms (up to 20/farm in one or two visits). Cecal and cloacal samples from each bird were aseptically collected and cultivated on a selective Simmons-citrate-adonitol agar medium and presumptive E. fergusonii colonies were then purified on MacConkey-sorbitol agar. Isolates were identified by API® 20E and by a duplex PCR method using E. fergusonii-specific primers.
Results: Of 207 presumptive isolates screened, 95 (45.9%) from 21 of the 32 screened farms (65.6%) were confirmed as E. fergusonii by API® 20E. Of these 95 E. Fergusonii isolates, 62 (68.1%) and 33 (36.3%) were from ceca and cloacae, respectively. E. fergusonii was found in 60.0% (6/10), 72.7% (8/11) and 63.6% (7/11) of farms in the east, north, and south Fraser Valley regions, respectively. The duplex PCR identified 182 E. fergusonii of 207 presumptive isolates (87.9%) from 29 farms, with 101 (60.1%) and 71 (42.3%) being from ceca and cloacae, respectively. Results showed that more E. fergusonii were detected by duplex PCR than by API® 20E and suggest that further investigations on E. fergusonii identification are warranted.
Significance: This study showed that in the investigated area, having dense broiler population, E. fergusonii is widespread which could have implications for both poultry and public health. The need for an accurate and efficient identification method is imperative.