Transmission of ESBL/AmpC-producing Escherichia coli from broiler chicken farms to surrounding areas.

Although previous studies have demonstrated high carriage of ESBL/AmpC-producing Escherichia coli in livestock, especially in broiler chickens, data on emission sources of these bacteria into the environment are still rare. Therefore, this study was designed to systematically investigate the occurrence of ESBL/AmpC-producing E. coli in slurry, air (inside animal houses), ambient air (outside animal houses) and on soil surfaces in the areas surrounding of seven ESBL/AmpC-positive broiler chicken fattening farms, including investigation of the possible spread of these bacteria via the faecal route and/or exhaust air into the environment. Seven German broiler fattening farms were each investigated at three points in time (3-36 h after restocking, 14-18 and 26-35 days after housing) during one fattening period. The occurrence of ESBL/AmpC genes in the investigated samples was confirmed by PCR, detecting blaCTX-M, blaSHV, blaTEM and blaCMY-genes, and, if necessary, by sequencing and/or the disc diffusion method. The results showed a wide spread of ESBL/AmpC-producing E. coli in broiler farms, as well as emissions into the surroundings. 12 out of 14 (86%) slurry samples were positive for ESBL/AmpC-producing E. coli. Additionally, 28.8% (n=23/80) of boot swabs taken from various surfaces in the areas surrounding of the farms as well as 7.5% (n=3/40) of the exhaust air samples turned out to be positive for these microorganisms. Moreover, a small proportion of air samples from inside the barns were ESBL/AmpC-positive. By comparing selected isolates using pulsed field gel electrophoresis, we proved that faecal and airborne transfer of ESBL/AmpC-producing microorganisms from broiler fattening farms to the surrounding areas is possible. Two isolates from farm G2 (slurry and boot swab 50 m downwind), two isolates from farm G3 (slurry and individual animal swab) as well as two isolates from farm G6 (air sample in the barn and air sample 50 m downwind) showed 100% similarity in PFGE analysis.

Laube H ，Friese A ，von Salviati C ，Guerra B ，Rösler U ... -  《-》

Emission of ESBL/AmpC-producing Escherichia coli from pig fattening farms to surrounding areas.

The presence of ESBL/AmpC-producing Escherichia coli in livestock such as pigs has been known for some time. However, to date there is little information about the transmission of these resistant bacteria between pig farms and their surroundings. Thus, the aim of this study was to explore this topic by investigating seven German pig fattening farms. Samples from outside (including ground surfaces, ambient air, slurry and digestate from biogas plants) and, in parallel, from inside the pig barns (including pig feces, dust, barn air, flies and mice feces) were examined for ESBL/AmpC-producing E. coli and selected isolates were compared by pulsed-field gel electrophoresis (PFGE) analysis. 14/17 (82.4%) slurry samples and three of four samples of digestate from biogas plants tested positive for ESBL/AmpC-producing E. coli. In the vicinity of the pig barns these resistant bacteria were detected in 14/87 (16.1%) boot swabs taken from various ground surfaces and in 2/36 (6%) ambient air samples. Inside the pig barns, 6/63 (9.5%) barn air samples and a small proportion of flies and mice feces samples were ESBL/AmpC-positive. PFGE analysis proved fecal emission as well as a possible spread via flies, as identical ESBL-E. coli isolates were detected in slurry and on fertilized fields, as well as in flies and pooled feces from inside the barn and slurry. Contaminated slurry presented the major emission source for ESBL/AmpC-producing E. coli in the pig fattening farms, but a spread via the airborne route or via different vectors also seems possible.

von Salviati C ，Laube H ，Guerra B ，Roesler U ，Friese A ... -  《-》

Faecal occurrence and emissions of livestock-associated methicillin-resistant Staphylococcus aureus (laMRSA) and ESbl/AmpC-producing E. coli from animal farms in Germany.

Friese A ，Schulz J ，Laube H ，von Salviati C ，Hartung J ，Roesler U ... -  《BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT》

Extended-Spectrum Beta-Lactamase-/AmpC Beta-Lactamase-Producing Enterobacteriaceae in Broiler Farms: Transmission Dynamics at Farm Level.

Daehre K ，Projahn M ，Semmler T ，Roesler U ，Friese A ... -  《-》

Extended-spectrum beta-lactamases (ESBL)/AmpC beta-lactamases-producing Escherichia coli in German fattening pig farms: a longitudinal study.

Von Salviati C ，Friese A ，Roschanski N ，Laube H ，Guerra B ，Käsbohrer A ，Kreienbrock L ，Roesler U ... -  《BERLINER UND MUNCHENER TIERARZTLICHE WOCHENSCHRIFT》