ArticlePoultry science2026
Antimicrobial resistance characteristics of enterococcus and analysis of intra-farm transmission associations in large-scale laying hen production.
Article in Poultry science, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The emergence and transmission of antimicrobial resistance (AMR) in layer production has drawn considerable attention. Enterococcus spp. are recognized as indicator bacteria for AMR, and systematic investigation of these organisms can help elucidate the dynamics of AMR risks. In this study, a total of 1,016 samples were collected at multiple time points and from various sites across the production chain on a large-scale layer farm. Enterococci were isolated and cultured, and selected strains were subjected to antimicrobial susceptibility testing and whole-genome sequencing. The overall isolation rate of Enterococcus was 80.0%, with the highest rate observed in floor samples (92.9%). The predominant resistance phenotypes were to macrolides, tetracyclines, and sulfonamides. Genome sequencing revealed that all sequenced E. faecalis strains harbored tet(L), lsa(A), and optrA, whereas all E. faecium strains carried aac(6')-Ii and msr(C). Mobile genetic elements were present in 97.2% of the isolates, and the transposon Tn554 was identified in 13 strains across all production stages. Multilocus sequence typing (MLST) identified 12 sequence types (STs) among E. faecalis, with ST1024 predominating, and 7 STs among E. faecium, with ST92, ST1091, and ST160 being dominant. Single nucleotide polymorphism (SNP) analysis revealed high genetic homology between ST1024 strains isolated from farm workers and layer cloacal samples, between ST1091 strains from water and floor samples, and between ST160 strains from air and eggshell surfaces. These findings demonstrate genetic relatedness across different niches, suggesting potential within-farm transmission and pointing to cross-transmission risks of resistant Enterococcus between humans and layers, between feed/water and the environment, and between the environment and eggs. Furthermore, high homology detected between ST92 strains isolated from flies and workers five months apart indicates persistent transmission and colonization via biological vectors. Resistance phenotypes for enrofloxacin and sulfisoxazole were strongly associated with environmental samples, highlighting the farm environment as a critical potential control point for AMR risk mitigation. Leveraging whole-genome sequencing, this study explores the transmission risk of antimicrobial-resistant Enterococcus in layer production and provides insights for preventing AMR risks originating from layer farms.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.