RT Journal Article
T1 Day-old chicks are a source of antimicrobial resistant bacteria for laying hen farms
A1 Moreno Romo, Miguel Ángel
A1 García Soto, Silvia
A1 Hernández, Marta
A1 Bárcena Asensio, María Carmen
A1 Rodríguez Lázaro, David
A1 Ugarte Ruiz, María
A1 Domínguez Rodríguez, Lucas José
AB Antimicrobial resistant bacteria are rarely detected in laying hens and the objective of this longitudinal study was to test day-old chick as a source. Four different commercial batches raised on the same farm were monitored from day-old chick to laying hens using Escherichia coli as a model. Ten colonies from each of the eight samplings per batch were tested for antimicrobial susceptibility using 14 antimicrobials.Overall (313 isolates), higher resistance percentages were detected for tetracycline (26.8%), followed by sulphonamides (16.3%), ampicillin (16.0 %) and quinolones (10.9% and 9.3% for ciprofloxacin and nalidixic acid, respectively). Resistance percentages of bacteria from day-old chicks were higher than those of pullets and hens (p < 0.05) for tetracycline, sulphonamides, trimethoprim and chloramphenicol.Forty different phenotypic resistance profiles were detected, led by fully susceptible (182 isolates; 58.1%), and followed by single tetracycline (28 isolates; 8.9%) and ciprofloxacin/ nalidixic acid (11 isolates; 3.5%) profiles.By whole-genome sequencing, 17 genes and mutations of five chromosomal genes related to resistance were detected, the most frequent being tetA, blaTEM-1B and sul1.Using multilocus sequencing analysis, 58 different MLST types were detected, most of them only in a particular sample. The ST155 (27/142) was the most frequently detected, followed by ST10 (19/142) and ST48 (9/142).The fate on the farm of the detected E. coli populations in old-day chicks was not clear, but our data suggest that they did not remain in the predominant faecal population of pullets and laying hens.
PB Elsevier
SN 0378-1135
SN 1873-2542
YR 2019
FD 2019
LK https://hdl.handle.net/20.500.14352/111250
UL https://hdl.handle.net/20.500.14352/111250
LA eng
NO Moreno, M. A., García-Soto, S., Hernández, M., Bárcena, C., Rodríguez-Lázaro, D., Ugarte-Ruíz, M., & Domínguez, L. (2019). Day-old chicks are a source of antimicrobial resistant bacteria for laying hen farms. Veterinary microbiology, 230, 221–227. https://doi.org/10.1016/j.vetmic.2019.02.007
NO Ministerio de Economía y Competitividad (España)
DS Docta Complutense
RD 7 abr 2025