Competitive Exclusion Reduces Transmission and Excretion of Extended-Spectrum-β-Lactamase-Producing Escherichia coli in Broilers.
Extended-spectrum β-lactamases (ESBLs) and plasmid-mediated AmpC β-lactamases (pAmpC) are enzymes able to hydrolyze a large variety of β-lactam antibiotics, including third-generation cephalosporins and monobactams. Broilers and broiler meat products can be highly contaminated with ESBL- and pAmpC-producingEscherichia colistrains, also known as extended-spectrum cephalosporin (ESC)-resistantE. colistrains, and can be a source for human infections. As few data on interventions to reduce the presence of ESC-resistantE. coliin broilers are available, we used transmission experiments to examine the role of competitive exclusion (CE) on reducing transmission and excretion in broilers. A broiler model to study the transmission of ESC-resistantE. coliwas set up. Day-old chickens were challenged with an ESBL-producingE. colistrain isolated from healthy broilers in the Netherlands. Challenged and not challenged chicks were housed together in pairs or in groups, and ESBL-producingE. colitransmission was monitored via selective culturing of cloacal swab specimens. We observed a statistically significant reduction in both the transmission and excretion of ESBL-producingE. coliin chicks treated with the probiotic flora beforeE. colichallenge compared to the transmission and excretion in untreated controls. In conclusion, our results support the use of competitive exclusion as an intervention strategy to control ESC-resistantE. coliin the field.IMPORTANCEExtended-spectrum β-lactamases (ESBLs) and plasmid-mediated AmpC β-lactamases are a primary cause of resistance to β-lactam antibiotics among members of the familyEnterobacteriaceaein humans, animals, and the environment. Food-producing animals are not exempt from this, with a high prevalence being seen in broilers, and there is evidence pointing to a possible foodborne source for human contamination. We investigated the effect of administration of a commercial probiotic product as an intervention to reduce the amount of ESBL-producingEscherichia coliin broilers. Our results showed a substantial reduction in the level of colonization of broiler intestines by ESBL-producingE. coliafter administration of commercial probiotic product. The protective effect provided by these probiotics could be implemented on a larger scale in poultry production. Reductions in the levels of ESBL-producingEnterobacteriaceaein the food chain would considerably benefit public health.
Wageningen Bioveterinary Research, Lelystad, the Netherlands daniela.ceccarelli@wur.nl jeanet.vandergoot@wur.nl.
Daniela
D
Ceccarelli
Wageningen Bioveterinary Research, Lelystad, the Netherlands.
Alieda
A
van Essen-Zandbergen
Wageningen Bioveterinary Research, Lelystad, the Netherlands.
Bregtje
B
Smid
Wageningen Bioveterinary Research, Lelystad, the Netherlands.
Kees T
KT
Veldman
Wageningen Bioveterinary Research, Lelystad, the Netherlands.
Gert Jan
GJ
Boender
Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
Egil A J
EAJ
Fischer
Wageningen Bioveterinary Research, Lelystad, the Netherlands.|Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
Dik J
DJ
Mevius
Wageningen Bioveterinary Research, Lelystad, the Netherlands daniela.ceccarelli@wur.nl jeanet.vandergoot@wur.nl.
Jeanet A
JA
van der Goot
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002645:Chickens; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology / Q000635:transmission / Q000662:veterinary*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D009426:Netherlands; D011201:Poultry Diseases / Q000382:microbiology / Q000635:transmission*; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D001618:beta-Lactamases
ESBL; Escherichia coli; broiler chicken; competitive exclusion; excretion; intervention; poultry; transmission; β-lactamases