Prevalence, Risk Factors, Antimicrobial Resistance and Molecular Characterization of Salmonella in Northeast Tunisia Broiler Flocks

This study was conducted in northeastern Tunisia to estimate both the prevalence and the risk factors of Salmonella in broiler flocks as well as to characterize the isolated multidrug-resistant (MDR) Salmonella strains. In the present study, a total number of 124 farms were sampled; Salmonella isolates were identified by the alternative technique VIDAS Easy Salmonella. The susceptibility of Salmonella isolates was assessed against 21 antimicrobials using the disk diffusion method on Mueller–Hinton agar using antimicrobial discs. Some antimicrobial resistance genes were identified using PCR. The prevalence rate of Salmonella infection, in the sampled farms, was estimated at 19.9% (64/322). Moreover, a total number of 13 different serotypes were identified. High rate of resistance was identified against nalidixic acid (82.85%), amoxicillin (81.25%), streptomycin (75%), and ciprofloxacin (75%). Alarming level of resistance to ertapenem (12.5%) was noticed. A total of 87.5% (56/64) of isolated strains were recognized as MDR. Three MDR strains were extended-spectrum β-lactamases (ESBL)-producers and three MDR strains were cephalosporinase-producers. The blaCTX-M gene was amplified in all the three ESBL strains. The qnrB gene was not amplified in fluoroquinolones-resistant strains. The tetA and tetB genes were amplified in 5% (2/40) and 2.5% (1/40) of tetracycline-resistant strains, respectively. The dfrA1 gene was amplified in five of the 20 trimethoprim-resistant strains. The mcr-1, mcr-2, mcr-3, mcr-4, and mcr-5 genes were not amplified in any of the phenotypically colistin-resistant strains. In terms of integrase genes int1 and int2, only gene class 2 was amplified in 11% (7/64) of analyzed strains. Risk factors, such as the poor level of cleaning and disinfection, the lack of antimicrobial treatment at the start of the breeding, and a crawl space duration lower than 15 days, were associated with high Salmonella infection in birds. These data should be considered when preparing salmonellosis control programs in Tunisian broiler flocks.

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Staphylococci among Wild European Rabbits from the Azores: A Potential Zoonotic Issue?

Journal of Food Protection ◽

10.4315/0362-028x.jfp-19-423 ◽

2020 ◽

Vol 83 (7) ◽

pp. 1110-1114 ◽

Cited By ~ 1

Author(s):

MARGARIDA SOUSA ◽

VANESSA SILVA ◽

ADRIANA SILVA ◽

NUNO SILVA ◽

JESSICA RIBEIRO ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Resistance Genes ◽

Meca Gene ◽

Diffusion Method ◽

Coagulase Negative Staphylococci ◽

Spa Typing ◽

Disk Diffusion Method ◽

Genetic Lineages ◽

Antimicrobial Resistance Genes ◽

European Rabbits

ABSTRACT The prevalence and diversity of Staphylococcus species from wild European rabbits (Oryctolagus cuniculus) in the Azores were investigated, and the antibiotic resistance phenotype and genotype of the isolates were determined. Nasal samples from 77 wild European rabbits from São Jorge and São Miguel islands in Azores were examined. Antibiotic susceptibility of the isolates was determined using the Kirby-Bauer disk diffusion method, and the presence of antimicrobial resistance genes and virulence factors was determined by PCR. The genetic lineages of S. aureus isolates were characterized by spa typing and multilocus sequence typing. A total of 49 staphylococci were obtained from 35 of the 77 wild rabbits. Both coagulase-positive (8.2%) and coagulase-negative (91.8%) staphylococci were detected: 4 S. aureus, 17 S. fleurettii, 13 S. sciuri, 7 S. xylosus, 4 S. epidermidis, and 1 each of S. simulans, S. saprophyticus, S. succinus, and S. equorum. The four S. aureus isolates showed methicillin susceptibility and were characterized as spa type t272/CC121, Panton-Valentine leukocidin negative, and hlB positive. Most of the coagulase-negative staphylococci showed resistance to fusidic acid and beta-lactams, and multidrug resistance was identified especially among S. epidermidis isolates. The mecA gene was detected in 20 isolates of the species S. fleurettii and S. epidermidis, associated with the blaZ gene in one S. epidermidis isolate. Five antimicrobial resistance genes were detected in one S. epidermidis isolate (mecA,dfrA,dfrG,aac6′-aph2′′, and ant4). Our results highlight that wild rabbits are reservoirs or “temporary hosts” of Staphylococcus species with zoonotic potential, some of them carrying relevant antimicrobial resistances. HIGHLIGHTS

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Antimicrobial Resistance and Virulence Determination of Enterococcus spp. Obtained from Hospital Environment in Iran

10.21203/rs.3.rs-123398/v1 ◽

2020 ◽

Author(s):

Saba Asgharzadeh Marghmalek ◽

Reza Valadan ◽

Mehrdad Gholami ◽

Mohtaram Nasrolahei ◽

Hamid Reza Goli

Keyword(s):

Antimicrobial Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Hospital Environment ◽

Diffusion Method ◽

Virulence Determinants ◽

Environmental Isolates ◽

Disk Diffusion Method ◽

Antimicrobial Resistance Genes

Abstract Background: The role of the hospital environment as a source of pathogenic bacteria in recent studies has been poorly investigated. This study investigated the distribution of antimicrobial resistance genes and virulence determinants in Enterococcus species isolated from hospital environment in Sari, Iran. Method: Overall, 90 enterococci strains were obtained from high touch surfaces of four hospitals in Sari, Iran. These environmental samples were obtained from bathroom, beds, tables, doorknobs, room keys, wheelchair and walls in the patient and staff’s rooms. The resistance profile of the isolates was determined by disk diffusion method. Seven resistance genes and two virulence associated genes were evaluated molecularly by multiplex PCR. Results: According to the PCR, 42 (46.66%) of them were E. faecalis and 48 (53.33%) others were detected as E. faecium. Also, 28 (66.6%) E. faecalis and 18 (37.5%) E. faecium isolates were multidrug-resistant (MDR). Among all 90 environmental isolates 54 (60%), 54 (60%), 8 (8.8%), 8 (8.8%), 60 (66.6%), 26 (28.8%), and 24 (26.6%) isolates contained tetM, tetL, vanA, vanB, ermB, aac(6´)-Ie-aph(2´´)-Ia, and aph (3´)-IIIa, respectively. Moreover, all isolates were investigated for the presence of virulence genes and 88 (97.7%) of isolates had esp gene, and 16 (17.7%) had ace.Conclusions: This report showed that the environmental isolates of Enterococcus are the major sources of antibiotic resistance genes that can transfer them to the clinical isolates of bacteria in hospital settings. An effective following strategy should be organized to clearance and stop emergence of these pathogenic bacteria.

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Frequency and Characterization of Antimicrobial Resistance and Virulence Genes of Coagulase-Negative Staphylococci from Wild Birds in Spain. Detection of tst-Carrying S. sciuri Isolates

Microorganisms ◽

10.3390/microorganisms8091317 ◽

2020 ◽

Vol 8 (9) ◽

pp. 1317

Author(s):

Laura Ruiz-Ripa ◽

Paula Gómez ◽

Carla Andrea Alonso ◽

María Cruz Camacho ◽

Yolanda Ramiro ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Virulence Genes ◽

Meca Gene ◽

Virulence Gene ◽

Wild Birds ◽

Diffusion Method ◽

Coagulase Negative Staphylococci ◽

Disk Diffusion Method ◽

Resistance Phenotype ◽

Antimicrobial Resistance Genes

The objective of this study was to determine the prevalence and diversity of coagulase-negative staphylococci (CoNS) species from wild birds in Spain, as well as to analyze the antimicrobial resistance phenotype/genotype and the virulence gene content. During 2015–2016, tracheal samples of 242 wild birds were collected in different regions of Spain for staphylococci recovery. The species identification was performed using MALDI-TOF. The antimicrobial resistance phenotype and genotype was investigated by the disk diffusion method and by PCR, respectively. The presence of the virulence genes lukF/S-PV, tst, eta, etb, etd and scn was investigated by PCR. Moreover, CoNS carrying the mecA gene were subjected to SCCmec typing. Of the tested animals, 60% were CoNS-carriers, and 173 CoNS isolates were recovered from the 146 positive animals, which belonged to 11 species, with predominance of S. sciuri (n = 118) and S. lentus (n = 25). A total of 34% of CoNS isolates showed a multidrug resistance phenotype, and 42 mecA-positive methicillin-resistant CoNS (MRCoNS) were detected. The isolates showed resistance to the following antimicrobials (percentage of resistant isolates/antimicrobial resistance genes detected): penicillin (49/ blaZ, mecA), cefoxitin (24/ mecA), erythromycin and/or clindamycin (92/ erm(B), erm(C), erm(43), msr(A), mph(C), lnu(A), lsa(B), vga(A) and sal(A)), gentamicin and/or tobramycin (5/ aac(6′)-Ie-aph(2″)-Ia, ant(4′)-Ia), streptomycin (12/str), tetracycline (17/ tet(K), tet(L), tet(M)), ciprofloxacin (4), chloramphenicol (1/ fexA), fusidic acid (86/ fusB, fusD) and trimethoprim–sulfamethoxazole (1/ dfrK). None of the isolates harbored the lukF/S-PV, eta, etb, etd and scn genes, but two S. sciuri isolates (1%) carried the tst gene. Wild birds are frequently colonized by CoNS species, especially S. sciuri. We identified scavenging on intensively produced livestock and feeding on landfills as risk factors for CoNS carriage. High proportions of MRCoNS and multidrug resistant CoNS were detected, which coupled with the presence of important virulence genes is of concern.

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Antimicrobial Resistance Profile of Salmonella and Listeria monocytogenes Isolated from Products Marketed on the Border of Brazil with Argentina and Uruguay

Journal of Food Protection ◽

10.4315/jfp-20-176 ◽

2020 ◽

Vol 83 (11) ◽

pp. 1941-1946

Author(s):

JULIANO GONÇALVES PEREIRA ◽

VANESSA MENDONÇA SOARES ◽

LEONARDO ERENO TADIELO ◽

TASSIANA RAMIRES ◽

WLADIMIR PADILHA da SILVA

Keyword(s):

Listeria Monocytogenes ◽

Antimicrobial Resistance ◽

Foodborne Pathogens ◽

Penicillin G ◽

Diffusion Method ◽

Salmonella Spp ◽

Disk Diffusion Method ◽

Resistance Profile ◽

Antimicrobial Resistance Profile ◽

Antimicrobial Resistance Genes

ABSTRACT We aimed to perform serotyping and the antimicrobial resistance profile of Salmonella spp. and Listeria monocytogenes strains isolated from raw meats imported illegally into Brazil along the borders of Argentina and Uruguay. Distinct isolates of Salmonella spp. (n = 6) and L. monocytogenes (n = 25) obtained from 270 of these food products of earlier work were serotyped and tested for antimicrobial resistance by agar disk diffusion method. For strains that were considered phenotypically resistant, antimicrobial resistance genes were investigated: strA, strB, floR, tetA, tetB, blaZ, blaTEM, ermB, ermC, and ereB to Salmonella sp. and blaZ and mecA to L. monocytogenes. All Salmonella isolates were identified as Salmonella Infantis; they were multidrug resistant and harbored the genes blaTEM (n = 6), strA (n = 1), strB (n = 1), floR (n = 1), ermB (n = 1), tetA (n = 3), and tetB (n = 3). L. monocytogenes isolates belonged to serovars 1/2a (n = 1), 1/2b (n = 14), 1/2c (n = 2), and 4b (n = 8), showed resistance only to penicillin G (n = 12), and did not show the blaZ and mecA genes. The results demonstrated that illegal foods that are commercialized in the Brazilian international border with Argentina and Uruguay may harbor foodborne pathogens, and some of them have multidrug resistance characteristics, such as Salmonella, emphasizing the need for greater control of international food transit in Brazil, especially in the region evaluated. HIGHLIGHTS

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Molecular Characterization of Cephalosporin and Fluoroquinolone Resistant Salmonella choleraesuis Isolated from Patients with Systemic Salmonellosis in Thailand

Antibiotics ◽

10.3390/antibiotics10070844 ◽

2021 ◽

Vol 10 (7) ◽

pp. 844

Author(s):

Pichapak Sriyapai ◽

Chaiwat Pulsrikarn ◽

Kosum Chansiri ◽

Arin Nyamniyom ◽

Thayat Sriyapai

Keyword(s):

Antimicrobial Resistance ◽

Public Health Problem ◽

Multidrug Resistant ◽

Pulse Field ◽

Diffusion Method ◽

Third Generation ◽

Disk Diffusion Method ◽

Salmonella Choleraesuis ◽

Antimicrobial Resistance Genes ◽

Third Generation Cephalosporins

The antimicrobial resistance of nontyphoidal Salmonella has become a major clinical and public health problem. Southeast Asia has a high level of multidrug-resistant Salmonella and isolates resistant to both fluoroquinolone and third-generation cephalosporins. The incidence of co-resistance to both drug classes is a serious therapeutic problem in Thailand. The aim of this study was to determine the antimicrobial resistance patterns, antimicrobial resistance genes and genotypic relatedness of third-generation cephalosporins and/or fluoroquinolone-resistant Salmonella Choleraesuis isolated from patients with systemic salmonellosis in Thailand. Antimicrobial susceptibility testing was performed using the agar disk diffusion method, and ESBL production was detected by the combination disc method. A molecular evaluation of S. Choleraesuis isolates was performed using PCR and DNA sequencing. Then, a genotypic relatedness study of S. Choleraesuis was performed by pulse field gel electrophoresis. All 62 cefotaxime-resistant S. Choleraesuis isolates obtained from 61 clinical specimens were multidrug resistant. Forty-four isolates (44/62, 71.0%) were positive for ESBL phenotypes. Based on the PCR sequencing, 21, 1, 13, 23, 20 and 6 ESBL-producing isolates harboured the ESBL genes blaCTX-M-14, blaCTX-M-15, blaCTX-M-55, blaCMY-2, blaACC-1 and blaTEM-1, respectively. This study also found that nine (9/62, 14.5%) isolates exhibited co-resistance to ciprofloxacin and cefotaxime. All of the co-resistant isolates harboured at least one PMQR gene. The qnr genes and the aac(6′)-Ib-cr gene were the most prevalent genes detected. The QRDR mutation, including the gyrA (D87Y and D87G) and parC (T57S) genes, was also detected. PFGE patterns revealed a high degree of clonal diversity among the ESBL-producing isolates.

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Prevalencia de especies zoonóticas de Arcobacter en cerdos a nivel de matadero en Ecuador

Revista Mvz Córdoba ◽

10.21897/rmvz.1798 ◽

2020 ◽

pp. e1798

Author(s):

Rosa Janneth Simaluiza-Masabanda ◽

Jimmy Fernández-Cajamarca ◽

Heriberto Fernandez

Keyword(s):

Antimicrobial Resistance ◽

Multiplex Pcr ◽

High Resistance ◽

Probabilistic Method ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Fecal Carriage ◽

Microbiological Methods ◽

Southern Ecuador ◽

Resistant Strains

Objective. To establish the prevalence, diversity and antimicrobial resistance of the zoonotic species of Arcobacter in healthy pigs at slaughterhouse level. Material and Methods. Fifty fecal samples were taken by rectal swabs from healthy pigs, before the beginning of the slaughter at the slaughterhouse of Loja city, Southern Ecuador. Sampling was performed using a non-probabilistic method for convenience. Isolation of Arcobacter strains was done by microbiological methods and species identification using biochemical and molecular (multiplex PCR) tests. Antimicrobial behavior was performed using the disk diffusion method. Results. The four zoonotic species of Arcobacter were found. The isolation rates were A. thereius (18.0%), A. skirrowii (18.0%), A. cryaerophilus (6.0%) and A. butzleri (2.0%). High resistance to ciprofloxacin was found and multi-resistant strains were isolated from these four species. Conclusions. The fecal carriage of the zoonotic species of Arcobacter was demonstrated in pigs at slaughterhouse level. These species showed high resistance to ciprofloxacin being isolated muti-resistant strains among these four species.

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Antimicrobial Resistance in Enterococcus spp. Strains Isolated from Organic Chicken, Conventional Chicken, and Turkey Meat: A Comparative Survey

Journal of Food Protection ◽

10.4315/0362-028x-70.4.1021 ◽

2007 ◽

Vol 70 (4) ◽

pp. 1021-1024 ◽

Cited By ~ 30

Author(s):

J. M. MIRANDA ◽

M. GUARDDON ◽

A. MONDRAGÓN ◽

B. I. VÁZQUEZ ◽

C. A. FENTE ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Common Species ◽

Multidrug Resistant ◽

Chicken Meat ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Turkey Meat ◽

Enterococcus Spp ◽

Resistant Strains ◽

Resistance Data

The mean counts of Enterococcus spp. were determined for 30 samples each of organic chicken meat, conventional chicken meat, and turkey meat, and differences for Enterococcus contamination in meat were determined. Two enterococci strains from each sample were isolated to obtain a total of 180 strains, and resistance to ampicillin, chloramphenicol, doxycycline, ciprofloxacin, erythromycin, gentamicin, nitrofurantoin, and vancomycin was determined by a disk diffusion method. Average counts obtained showed that Enterococcus mean counts from organic chicken meat (3.18 log CFU/g) were significantly higher than those obtained from conventional chicken meat (2.06 log CFU/g) or conventional turkey meat (1.23 log CFU/g). However, the resistance data obtained showed that isolates from organic chicken meat were less resistant than enterococci isolates from conventional chicken meat to ampicillin (P = 0.0067), chloramphenicol (P = 0.0154), doxycycline (P = 0.0277), ciprofloxacin (P = 0.0024), erythromycin (P = 0.0028), and vancomycin (P = 0.0241). In addition, isolates from organic chicken were less resistant than conventional turkey meat isolates to ciprofloxacin (P = 0.001) and erythromycin (P = 0.0137). Multidrug-resistant isolates were found in every group tested, but rates of multidrug-resistant strains were significantly higher in conventional chicken and turkey than those obtained from organic chicken meat. Enterococcus faecalis was the most common species isolated from organic chicken (36.67%), whereas Enterococcus durans was the most common species isolated from conventional chicken (58.33%) and turkey (56.67%). The rates obtained for antimicrobial resistance suggest that although organic chicken meat may have higher numbers of Enterococcus, these bacteria present a lower level of antimicrobial resistance.

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First isolation of Enterococcus strains in pig faeces in Turkey and determination of antibiotic susceptibilities

Acta Veterinaria Brno ◽

10.2754/avb201382030231 ◽

2013 ◽

Vol 82 (3) ◽

pp. 231-235

Author(s):

Kemal Metiner ◽

Mine Anğ Küçüker ◽

Özden Büyükbaba Boral ◽

Özdem Anğ

Keyword(s):

Antimicrobial Resistance ◽

High Rate ◽

Diffusion Method ◽

Marmara Region ◽

Disk Diffusion Method ◽

Faecal Samples ◽

Enterococcus Casseliflavus ◽

Enterococcus Gallinarum ◽

Enterococcus Cecorum

In this trial,Enterococcusstrains were isolated from a total of 69 faecal samples obtained from 238 pigs (105 pigs < 6 months old and 133 > 6 months old) on three pig farms located in Istanbul and Tekirdag Provinces in the Marmara Region of Turkey in the summer season of 2003. Forty-seven of the isolates were determined asEnterococcus faecium(68%), 15 isolates asEnterococcus faecalis(21.7%), three isolates asEnterococcus gallinarum(4.3%) and one of each asEnterococcus hirae(1.4%),Enterococcus casseliflavus(1.4%),Enterococcus cecorum(1.4%)andEnterococcus sulfurens(1.4%). In addition, antimicrobial susceptibilites of isolates were assessed through the disk diffusion method. Among 47E. faeciumisolates, 44 were determined to be resistant to erythromycin, 38 to ciprofloxacine, and three isolates were resistant to vancomycin. AllE. faecalisisolates were resistant to erythromycin (100%) and four were resistant to vancomycin (27%). FiveE. faecium(11%) and fiveE. faecalisisolates (33%) were found to exhibit intermediate resistance to vancomycin. In this study, isolates obtained from pig faeces were determined to exhibit a high rate of antimicrobial resistance. This study is the first report on isolation and determination of antimicrobial resistance of Enterocci in Turkey.

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Isolation, antimicrobial susceptibility patterns, and risk factors assessment of non-typhoidal Salmonella from apparently healthy and diarrheic dogs

BMC Veterinary Research ◽

10.1186/s12917-021-03135-x ◽

2022 ◽

Vol 18 (1) ◽

Author(s):

Belisa Usmael ◽

Bruk Abraha ◽

Sisay Alemu ◽

Bahar Mummed ◽

Adem Hiko ◽

...

Keyword(s):

Risk Factors ◽

Antimicrobial Resistance ◽

Rectal Swab ◽

Bacterial Load ◽

Diffusion Method ◽

Resistance Pattern ◽

Biochemical Tests ◽

Disk Diffusion Method ◽

Eastern Ethiopia ◽

Apparently Healthy

Abstract Background Dogs are one of the important asymptomatic carriers of antimicrobial resistant and potentially pathogenic strains of Salmonella. They can harbor large bacterial load in the intestines and mesenteric lymph nodes which can be shed in their feces with the possibility of transmission to humans. Therefore, a cross-sectional study was conducted with the objectives of estimating the prevalence of non-typhoidal Salmonella, assessing the risk factors for dog’s Salmonella carriage, and profiling the antimicrobial resistance pattern of Salmonella isolates among housed dogs in Harar town, Eastern Ethiopia. A total of 415 rectal swab samples were collected from randomly selected dogs. Samples were examined for non-typhoidal Salmonella using standard bacteriologic culture and biochemical tests. The disk diffusion method (Kirby-Bauer test) was employed to evaluate the isolates for their susceptibility against five antimicrobials. Results Non-typhoidal Salmonella were isolated from 26 (6.3%) of the rectal swab samples, with significantly higher occurrence in diarrheic (15.2%) than non-diarrheic (5.5%) dogs. The risk of Salmonella harboring was significantly higher in female dogs than in male dogs (OR = 2.5, p = 0.027). Dogs fecal shedding of Salmonella was relatively higher in households who used offal as a main feed type for their dogs (23.1%; 95% CI = 5–53.8) than those who used leftover food (10.1%; 95% CI = 5.7–16.1) and practiced mixed feeding system (17%; 95% CI = 7.6–30.8). Salmonella isolates showed higher resistance to ampicillin (41.7%), while all isolates were fully susceptible to gentamicin. Moreover, 58.3% of Salmonella isolates showed resistance to at least one of the tested antimicrobials. Majorities (72.7%) of the dog owners had no awareness on the risk of zoonotic salmonellosis from dog and all of the respondents use bare hand to clean dog kennel. Conclusion Our study reveals the importance of both diarrheic and apparently healthy housed dogs in the harboring and shedding of antimicrobial resistant non-typhoidal Salmonella. The risk of non-typhoidal Salmonella spread among pet owners is not negligible, especially in households who use offal as main feed type. Therefore, an integrated approach such as: proper dog handling practices; continuous evaluation of antimicrobial resistance; and rational use of antimicrobials in the field of veterinary sector are necessary to tackle the problem.

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Antimicrobial Resistance of Acetobacter and Komagataeibacter Species Originating from Vinegars

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph19010463 ◽

2022 ◽

Vol 19 (1) ◽

pp. 463

Author(s):

Eva Cepec ◽

Janja Trček

Keyword(s):

Antimicrobial Resistance ◽

Efflux Pump ◽

Close Contact ◽

Acetic Acid Bacteria ◽

Diffusion Method ◽

Growth Media ◽

Disk Diffusion Method ◽

Novel Foods ◽

Human Microbiota ◽

Antimicrobial Resistance Genes

Consumers’ preference towards healthy and novel foods dictates the production of organic unfiltered bottled vinegar that still contains acetic acid bacteria. After ingesting vinegar, the bacteria come into close contact with the human microbiota, creating the possibility of horizontal gene transfer, including genetic determinants for antibiotic resistance. Due to the global spread of antimicrobial resistance (AMR), we analyzed the AMR of Acetobacter and Komagataeibacter species originating mainly from vinegars. Six antibiotics from different structural groups and mechanisms of action were selected for testing. The AMR was assessed with the disk diffusion method using various growth media. Although the number of resistant strains differed among the growth media, 97.4%, 74.4%, 56.4%, and 33.3% of strains were resistant to trimethoprim, erythromycin, ciprofloxacin, and chloramphenicol, respectively, on all three media. Moreover, 17.9% and 53.8% of all strains were resistant to four and three antibiotics of different antimicrobial classes, respectively. We then looked for antimicrobial resistance genes in the genome sequences of the reference strains. The most common genetic determinant potentially involved in AMR encodes an efflux pump. Since these genes pass through the gastrointestinal tract and may be transferred to human microbiota, further experiments are needed to analyze the probability of this scenario in more detail.

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