ABSTRACT
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.
Subject(s)
Bacterial Proteins/genetics , Escherichia coli Infections/veterinary , Escherichia coli/isolation & purification , Swine Diseases/microbiology , beta-Lactam Resistance , beta-Lactamases/genetics , Animal Husbandry , Animals , Cluster Analysis , Diptera , Dogs , Electrophoresis, Gel, Pulsed-Field/veterinary , Environment , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/microbiology , Feces/microbiology , Manure/microbiology , Mice , Microbial Sensitivity Tests/veterinary , SwineABSTRACT
The presence of ESBL/AmpC-producing Enterobacteriaceae in healthy livestock, such as pigs, was frequently reported worldwide in the last years. The development and potential spread of these resistant microorganisms in farm animals is discussed critically. Therefore, the main objectives of this longitudinal study were to determine potential sources and prevalence dynamics of ESBL/AmpC-producing Escherichia coli in seven German ESBL/AmpC-positive conventional fattening pig farms in the course of the fattening period. Samples tested were taken at three different times within one finishing fattening period and included 20 individual faeces samples as well as various samples of the animals' housing environment such as pooled faeces, boot swabs, dust and environmental swabs. In individual faeces average carriage levels of 45%, 29% and 36% at the three sampling times were accompanied by decreasing faecal counts from 2.97 x 10(4) cfu/g at the first to 2.17 x 10(3) cfu/g at the third visit. In the animals' housing environment 47.6% of pooled faeces and boot swab samples respectively and 5.9% of environmental swabs but none of the dust samples were tested positive. Altogether 228 E. coli isolates were analysed by combination disc tests, PCR and partly via sequencing.Thereby, a novel gene bla(TEM-206) was detected. This study shows different detection levels of ESBL/AmpC-producing E. coli amongst the different farms and in the course of the fattening period. Pooled faeces and boot swab samples but not dust samples seem to be appropriate to assess the herd status of pigs with respect to ESBL/AmpC-producing Escherichia coli.
Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli/enzymology , Swine Diseases/microbiology , beta-Lactamases/biosynthesis , Animal Husbandry , Animals , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Dust , Environmental Microbiology , Escherichia coli/drug effects , Escherichia coli Infections/epidemiology , Feces/microbiology , Germany/epidemiology , Longitudinal Studies , Microbial Sensitivity Tests , Phenotype , Prevalence , Sus scrofa , Swine , Swine Diseases/epidemiologyABSTRACT
The occurrence of laMRSA (livestock-associated methicillin-resistant Staphylococcus aureus) and extended-spectrum beta-lactamase (ESBL) and/or plasmid-mediated AmpC beta-lactamase-producing (AmpC) Enterobacteriaceae in healthy livestock herds is known for some time.The spread of these bacteria in the environment is discussed critically.The object of this study was to determine the presence of these microorganisms in faeces of livestock as well as the discussion about a potential faecal emission. Therefore, faeces samples from 37 different MRSA positive livestock holdings were tested for MRSA. Furthermore, faeces samples from 50 farms with an unknown status regarding ESBL/AmpC-producing E. coli were screened for those resistant bacteria. LaMRSA was detected in samples of turkey (2/5, 40%) and broiler fattening farms (1/4, 25%) as well as in pig farms with higher detection frequencies in fattening farms (11/15, 73.3%) than in breeding farms (4/12, 33.3%). ESBL/AmpC-producing E. coli was found in all investigated eight broiler farms (100%), in nine out of 16 (56.3%) breeding pig as well as in six out of 10 (60%) dairy cattle herds and in seven of 16 (43.8%) fattening pig holdings. This presents the first detection of ESBL/AmpC-producing E. coli originating from healthy pigs, turkeys and broilers in Germany. In addition, samples of fertilized field surfaces were studied exemplarily for the presence of MRSA (n = 4) as well as ESBL/AmpC-producing E. coli (n = 2). Furthermore, slurry samples from four broiler and five pig farms were analysed for the latter. Both MRSA and ESBL/ AmpC-producing E. coli could be detected on the field surfaces, the last also in slurry samples. Faecal emissions from animal husbandry seem to be one possible route for the spread of these resistant microorganisms in the environment.
