scholarly journals Prevalence, virulence factor and antimicrobial resistance analysis of Salmonella Enteritidis from poultry and egg samples in Iran

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Hassan Bahramianfard ◽  
Abdollah Derakhshandeh ◽  
Zahra Naziri ◽  
Reza Khaltabadi Farahani
Keyword(s):  
Antimicrobial Resistance ◽  
Nalidixic Acid ◽  
Salmonella Enteritidis ◽  
Virulence Genes ◽  
Control Measures ◽  
Poultry Meat ◽  
Diffusion Method ◽  
Virulence Plasmid ◽  
Disk Diffusion Method ◽  
Zoonotic Risk

Abstract Background Salmonella enterica serovar Enteritidis (S. Enteritidis) is one of the most common serovars, associated with human salmonellosis. The food-borne outbreak of this bacterium is mainly related to the consumption of contaminated poultry meat and poultry products, including eggs. Therefore, rapid and accurate detection, besides investigation of virulence characteristics and antimicrobial resistance profiles of S. Enteritidis in poultry and poultry egg samples is essential. A total of 3125 samples (2250 poultry and 875 poultry egg samples), sent to the administrative centers of veterinary microbiology laboratories in six provinces of Iran, were examined for Salmonella contamination, according to the ISO 6579 guideline. Next, duplex PCR was conducted on 250 presumptive Salmonella isolates to detect invA gene for identification of the genus Salmonella and sdf gene for identification of S. Enteritidis. Subsequently, the S. Enteritidis isolates were examined for detection of important virulence genes (pagC, cdtB, msgA, spaN, tolC, lpfC, and spvC) and determination of antibiotic resistance patterns against nalidixic acid, trimethoprim-sulfamethoxazole, cephalothin, ceftazidime, colistin sulfate, and kanamycin by the disk diffusion method. Results Overall, 8.7 and 2.3% of poultry samples and 6.3 and 1.3% of eggs were contaminated with Salmonella species and S. Enteritidis, respectively. The invA and msgA genes (100%) and cdtB gene (6.3%) had the highest and the lowest prevalence rates in S. Enteritidis isolates. The spvC gene, which is mainly located on the Salmonella virulence plasmid, was detected in 50.8% of S. Enteritidis isolates. The S. Enteritidis isolates showed the highest and the lowest resistance to nalidixic acid (87.3%) and ceftazidime (11.1%), respectively. Unfortunately, 27.0% of S. Enteritidis isolates were multidrug-resistant (MDR). Conclusion The rate of contamination with Salmonella in the poultry and egg samples, besides the presence of antimicrobial resistant and MDR Salmonella isolates harboring the virulence genes in these samples, could significantly affect food safety and subsequently, human health. Therefore, continuous monitoring of animal-source foods, enhancement of poultry farm control measures, and limiting the use of antibiotics for prophylactic purposes in food producing animals, are essential for reducing the zoonotic risk of this foodborne pathogen for consumers and also choosing effective antibiotics for the treatment of salmonellosis.

scholarly journals Virulence-Associated Genes and Antimicrobial Resistance of Aeromonas hydrophila Isolates from Animal, Food, and Human Sources in Brazil

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Emily Moraes Roges ◽  
Verônica Dias Gonçalves ◽  
Maira Duarte Cardoso ◽  
Marcia Lima Festivo ◽  
Salvatore Siciliano ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Aeromonas Hydrophila ◽  
Pathogenic Bacteria ◽  
Virulence Genes ◽  
Animal Health ◽  
Diffusion Method ◽  
Aquatic Environments ◽  
Disk Diffusion Method ◽  
Polymerase Chain ◽  
Human Source

Aeromonads are natural inhabitants of aquatic environments and may be associated with various human or animal diseases. Its pathogenicity is complex and multifactorial and is associated with many virulence factors. In this study, 110 selected Aeromonas hydrophila isolates isolated from food, animals, and human clinical material from 2010 to 2015 were analyzed. Antimicrobial susceptibility testing was performed by the disk diffusion method, and polymerase chain reaction was conducted to investigate the virulence genes hemolysin (hlyA), cytotoxic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), aerolysin (aerA), and DNase-nuclease (exu). At least 92.7% of the isolates had one of the investigated virulence genes. Twenty different virulence profiles among the isolates were recognized, and the five investigated virulence genes were observed in four isolates. Human source isolates showed greater diversity than food and animal sources. Antimicrobial resistance was observed in 46.4% of the isolates, and multidrug resistance was detected in 3.6% of the isolates. Among the 120 isolates, 45% were resistant to cefoxitin; 23.5% to nalidixic acid; 16.6% to tetracycline; 13.7% to cefotaxime and imipenem; 11.8% to ceftazidime; 5.9% to amikacin, gentamicin, and sulfamethoxazole-trimethoprim; and 3.9% to ciprofloxacin and nitrofurantoin. Overall, the findings of our study indicated the presence of virulence genes and that antimicrobial resistance in A. hydrophila isolates in this study is compatible with potentially pathogenic bacteria. This information will allow us to recognize the potential risk through circulating isolates in animal health and public health and the spread through the food chain offering subsidies for appropriate sanitary actions.

scholarly journals Antimicrobial resistance in Salmonella enterica serovar Enteritidis in Morocco

2010 ◽  
Vol 4 (12) ◽  
pp. 804-809 ◽  
Author(s):  
Farida Ohmani ◽  
Khadija Khedid ◽  
Saad Britel ◽  
Aicha Qasmaoui ◽  
Reda Charof ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Nalidixic Acid ◽  
Salmonella Enterica ◽  
Inhibitory Concentration ◽  
Diffusion Method ◽  
Salmonella Enterica Serovar Enteritidis ◽  
Gastrointestinal Infections ◽  
Disk Diffusion Method ◽  
Resistance Patterns ◽  
Resistance Rates

Introduction: Salmonella enterica is recognised worldwide as one of the major agents of human gastrointestinal infections. The aim of the present work is to ascertain the antimicrobial susceptibilities of 150 Salmonella enterica serovar Enteritidis isolates from humans in Morocco during the period from 2000 to 2008. Methodology: Antimicrobial resistance determination was performed by disk diffusion method using seven antibiotics. The minimal inhibitory concentration (MIC) of ciprofloxacin was determined for nalidixic acid-resistant (NAR) isolates using E-test strips. Results: Sixty-one (42%) isolates were resistant to at least one class of antimicrobial agent. The largest numbers of resistant isolates were observed for nalidixic acid with 53 isolates (36%) followed by ampicillin with 7 isolates (5%), tetracycline with 6 isolates (4%), and trimethoprim/sulfamethoxazole with 2 isolates (1%).The resistant isolates were grouped in seven different resistance patterns of which two isolates were resistant to three antibiotics. Among the 53 (36%) NAR isolates, 37 (76%) had a reduced susceptibility to ciprofloxacin. Conclusion: Resistance rates of Salmonella enterica serovar Enteritidis from Morocco are generally low but the resistance to nalidixic acid is worryingly common. Continual surveillance of antibiotic resistance is of primary importance.

scholarly journals Virulence genes and antibiotic resistance of Pseudomonas aeruginosa isolated from patients in the Northwestern of Morocco

2019 ◽  
Vol 13 (10) ◽  
pp. 892-898
Author(s):  
Chaimae Elmouaden ◽  
Amin Laglaoui ◽  
Latifa Ennanei ◽  
Mohammed Bakkali ◽  
Mohammed Abid
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Nosocomial Infections ◽  
Virulence Genes ◽  
Health Workers ◽  
Control Measures ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Infection Control Measures ◽  
Antibiotic Susceptibility Patterns ◽  
High Level

Introduction: Pseudomonas aeruginosa is an ubiquitous bacterium causes various community-acquired and nosocomial infections. In this investigation, we aimed to screen the antibiotic susceptibility patterns and the prevalence of virulence factor genes in a set of Pseudomonas aeruginosa isolated from nosocomial and community-acquired infections in the Northwestern of Morocco. Methodology: A total of 155 of Pseudomonas aeruginosa strains were collected (January 2015 - December 2016) from nosocomial and community-acquired infections at hospital centers and clinical laboratories in the Northwestern of Morocco. Antimicrobial susceptibility test was performed by the standard disk diffusion method. In addition, PCR assays were used for screening five virulence encoding genes (lasB, algD, plcH, exoA, and exoS). Results: Our results revealed that high level of antimicrobial resistance was detected towards aztreonam (27.1%) followed by meropenem (14.2%). The resistance to imipenem was significantly higher in strains isolated from nosocomial infections (12.7%) than strains isolated from community-acquired infections (1.5%). The results highlighted that lasB (98.7%) and exoS (98.7%) were the most frequent virulence genes. Conclusions: This survey provides data about phenotypic and genotypic properties of Pseudomonas aeruginosa emerged in the Northwestern of Morocco. It could be helpful for the health workers to improve infection control measures and to establish a surveillance system.

scholarly journals 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

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.

Prevalence and antimicrobial resistance of Salmonella and Yersinia in the feces of hunted wildlife in Abeokuta, Nigeria

2019 ◽  
Vol 72 (4) ◽  
Author(s):  
Olufemi Ernest Ojo ◽  
Oluwaseyi Oluwadaisi Ogunjobi ◽  
Mufutau Atanda Oyekunle ◽  
Morenike Atinuke Dipeolu ◽  
Ebenezer Babatunde Otesile
Keyword(s):  
Antimicrobial Resistance ◽  
Clavulanic Acid ◽  
Nalidixic Acid ◽  
Biochemical Characterization ◽  
Diffusion Method ◽  
Wild Rodents ◽  
Culture Methods ◽  
Disk Diffusion Method ◽  
Amoxicillin Clavulanic Acid ◽  
Cricetomys Gambianus

Meat from wildlife contributes significantly to food security and income generation in many African communities. Salmonellae and yersiniae are important causes of foodborne infections. This study investigated the presence and antimicrobial resistance of salmonellae and yersiniae in the fecal contents of hunted wild rodents and ruminants at a wildlife meat-processing center in Abeokuta, Nigeria. Bacteria were isolated and identified by selective culture methods and biochemical characterization. Antimicrobial susceptibility was determined by the Kirby Bauer disk diffusion method. Salmonellae were isolated from 15 (9.8%) and yersiniae from 11 (7.2%) samples out of 153. Salmonellae were detected in nine cane rats (Thryonomys swinderianus), five royal antelopes (Neotragus pygmaeus) and one African giant rat (Cricetomys gambianus). Yersiniae were detected in eight cane rats, two royal antelopes and one waterbuck (Kobus ellipsiprymnus). The levels of resistance in Salmonella isolates were 100% for ampicillin and ceftiofur, 93.3% for tetracycline, 33.3% for cefotaxime, 26.7% for ceftazidime, 13.3% for amoxicillin/clavulanic acid, nalidixic acid and sulfamethoxazole/trimethoprim, and 6.7% for gentamicin, streptomycin and norfloxacin. The levels of resistance in yersiniae isolates were 81.8% for ampicillin, 72.7% for ceftiofur, 63.6% for nalidixic acid, 54.5% for cefotaxime, ceftazidime and sulfamethoxazole/trimethoprim, 36.4% for tetracycline, 27.3% for amoxicillin/clavulanic acid and streptomycin, 18.2% for ciprofloxacin, and 9.1% for chloramphenicol and gentamicin. All the isolates showed multiresistance to antimicrobials from at least three different classes. The detection of antimicrobial resistant salmonellae and yersiniae in wildlife is of veterinary and public health significance as these organisms can be transmitted to domestic animals and humans.

Occurrence and Antimicrobial Resistance Profiles of Salmonella Species in Retail Meat Products

2010 ◽  
Vol 73 (9) ◽  
pp. 1613-1617 ◽  
Author(s):  
SEZA ARSLAN ◽  
AYLA EYI
Keyword(s):  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
Meat Products ◽  
Ground Beef ◽  
Poultry Meat ◽  
Diffusion Method ◽  
Antimicrobial Drugs ◽  
Disk Diffusion Method ◽  
Serovar Typhimurium ◽  
Retail Meat

In the present study, a total of 225 retail meat products (poultry meat, ground beef, and beef samples) were tested for the prevalence of Salmonella. Of these, 50 (22.2%) were positive for Salmonella. Overall, the pathogen was detected in 22 (29.3%) samples of poultry meat (n = 75), 16 (21.3%) samples of ground beef (n = 75), and 12 (16%) samples of beef (n = 75). The most common isolate was Salmonella enterica serovar Typhimurium (9.8%), followed by S. bongori species (8.9%) and S. enterica subsp. diarizonae (3.5%). The Salmonella strains isolated were also examined for antimicrobial resistance patterns and production of β-lactamase enzyme. The resistance levels of the isolates against 14 different antimicrobial agents were tested by the disk diffusion method. None of the strains exhibited resistance to cefotaxime, ciprofloxacin, norfloxacin, or levofloxacin. However, the highest resistance rates in the meat isolates were 64% each for ampicillin and cephazolin and 56% for amoxicillin–clavulanic acid. A total of 62% of the 50 Salmonella strains were multiresistant to three or more antimicrobial agents. The exhibited multiple resistance to four or more antimicrobial drugs was 32%. Furthermore, none of the isolates had β-lactamase enzyme activity.

Prevalence and Antimicrobial Resistance of Listeria monocytogenes Isolated in Chicken Slaughterhouses in Northern Greece

2011 ◽  
Vol 74 (6) ◽  
pp. 1017-1021 ◽  
Author(s):  
I. SAKARIDIS ◽  
N. SOULTOS ◽  
E. IOSSIFIDOU ◽  
A. PAPA ◽  
I. AMBROSIADIS ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Listeria Monocytogenes ◽  
Antimicrobial Resistance ◽  
Nalidixic Acid ◽  
Random Amplified Polymorphic Dna ◽  
The Other ◽  
Diffusion Method ◽  
Northern Greece ◽  
Disk Diffusion Method ◽  
High Prevalence

This study was conducted to determine the prevalence and antimicrobial resistance of Listeria monocytogenes recovered from chicken carcasses in slaughterhouses in Northern Greece. A total of 100 poultry samples (300 carcasses) were examined for Listeria spp. The samples were neck skin taken from four different slaughterhouses in Northern Greece. Forty samples were also taken from the environment of the slaughterhouses. Identification of L. monocytogenes was carried out by PCR and fingerprinting of the isolates by random amplified polymorphic DNA. L. monocytogenes strains isolated from chicken carcasses and from the environment of the slaughterhouses were also examined for antibiotic resistance. Fifty-five isolates of L. monocytogenes were tested for susceptibility to 20 antibiotics using the disk diffusion method. Listeria spp. were present in 99 of the poultry samples tested (99%), and 38 yielded L monocytogenes (38%). L. monocytogenes was also isolated in 80% of samples from the environment of a certain slaughterhouse, while the other slaughterhouses were found to be contaminated only with Listeria spp. All isolates were resistant to nalidixic acid and oxolinic acid, the majority of them to clindamycin, and only a few to tetracycline and oxytetracycline, whereas they were found to be susceptible to all other antimicrobials. The results of this study demonstrate a high prevalence of L. monocytogenes contamination in chicken carcasses, and all isolates were found to be sensitive to the antimicrobials most commonly used to treat human listeriosis.

scholarly journals Antimicrobial Resistance and Virulence Factors of Campylobacter coli Isolated from Chicken in Côte d’Ivoire

2020 ◽  
pp. 86-92
Author(s):  
Goualié Gblossi Bernadette ◽  
Bakayoko Souleymane ◽  
Konan Marie-Pierre Laure
Keyword(s):  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Virulence Gene ◽  
Poultry Meat ◽  
Diffusion Method ◽  
Campylobacter Coli ◽  
Hand Detection ◽  
Disk Diffusion Method ◽  
Microbiological Methods ◽  
Genotypic Analysis

Aims: Campylobacters species are major causes of gastroenteritis in human. The main risk factor of infection is consumption of contaminated or by cross-contaminated poultry meat. The aims of this study were to analyze antimicrobial profile and virulence factors associated to Campylobacter coli isolated from chicken’s ceaca in commercial slaughter in Abidjan. Methodology: A total of 336 chicken ceaca samples were collected from market of two municipality of Abidjan and were examined by conventional microbiological methods and molecular test using PCR. The antibiotic susceptibility tests of the isolates were determined by disk diffusion method the presence of virulence genes was examined using simple PCR method. Results: From these samples, 210/336 (62.50%) were positives for Campylobacter. Among the isolates, 53 strains confirmed as C. coli by using PCR detection were used for phenotypic and genotypic analysis. Of these strains, 51/53 were positive for one or more antibiotics molecules tested. The highest rate of antimicrobial resistance was found for nalidixic acid 51/53 (96.22%), tetracyclin 49/53 (92.45%) and ciprofloxacin 38/53 (71.69%). Moreover, MDR including 3, 4, 5 and 6 antibiotics families was detected in 11/53 (20.75%) of isolates. On the other hand, detection of virulence gene shows presence of cadF gene in 86.01% of isolates while 82.21% were positive for the three cdt (A, B and C) genes. Conclusion: We reported in this study the presence of high pathogenic Campylobacter coli contamination of the studied chickens. Molecular identification of the bacteria was performed and determination of high resistance to antimicrobials of the fluoroquinolone family was revealed.

scholarly journals Salmonella contamination, serovars and antimicrobial resistance profiles of cattle slaughtered in South Africa

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Evelyn Madoroba ◽  
Daniel Kapeta ◽  
Awoke K. Gelaw
Keyword(s):  
Public Health ◽  
Antimicrobial Resistance ◽  
South African ◽  
Environmental Samples ◽  
Salmonella Enteritidis ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Intestinal Contents ◽  
Microbiological Techniques ◽  
Salmonella Serovars

Antimicrobial resistant Salmonella are among the leading causes of foodborne infections. Our aim was to determine Salmonella contamination during cattle slaughter in South African rural abattoirs (n = 23) and environmental samples. Furthermore, antimicrobial resistance patterns of the Salmonella isolates were determined. Samples of cattle faeces (n = 400), carcass sponges (n = 100), intestinal contents (n = 62), hides (n = 67), and water from the abattoirs (n = 75) were investigated for Salmonella species using microbiological techniques and species-specific polymerase chain reaction targeting the invA gene. In total 92 Salmonella species isolates were recovered. The Salmonella mean frequency of occurrence on hides, carcasses, and intestinal contents was 35.37% (n = 81). Eleven faecal samples (2.75%) tested positive for Salmonella. The predominant serovar was Salmonella Enteritidis. Diverse serovars that were identified on carcasses were not necessarily found on the hides and intestinal contents. The inconsistent occurrence of the diverse Salmonella serovars on hides, carcasses, and intestinal contents implies that in addition to carriage on hides and in intestinal contents, other external factors also play an important role regarding carcass contamination. The 92 Salmonella were serotyped and tested for susceptibility towards the following antimicrobials: ampicillin, cefotaxime, enrofloxacin, kanamycin, and oxytetracycline using the disk diffusion method. Most Salmonella (n = 66; 71.7%) isolates were resistant to at least one antimicrobial with highest resistance observed towards oxytetracycline (51.90%), which highlights the need for strict hygiene during slaughter and prudent antimicrobial use during animal production. In conclusion, cattle slaughtered in South African rural abattoirs harbour diverse Salmonella serovars that are resistant to antimicrobials, which could be a public health risk. The findings should assist policymakers with improving implementation of hygienic slaughter of cattle in rural abattoirs, which is paramount from socioeconomic, public health, and epidemiological standpoints.Keywords: Salmonella; Cattle; Rural abattoirs; slaughter; Multidrug resistance; Environmental samples

Occurrence and Phenotypic and Molecular Characterization of Antimicrobial Resistance of Salmonella Isolates from Food in Tunisia

2019 ◽  
Vol 82 (7) ◽  
pp. 1166-1175 ◽  
Author(s):  
AMAL BEN HASSENA ◽  
MARIAM SIALA ◽  
SONDA GUERMAZI ◽  
SONIA ZORMATI ◽  
RADHOUANE GDOURA ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Salmonella Enteritidis ◽  
Foodborne Pathogen ◽  
Public Health Problem ◽  
Gene Families ◽  
Food Samples ◽  
Diffusion Method ◽  
Disk Diffusion Method ◽  
Salmonella Infections ◽  
Extended Spectrum

ABSTRACT Salmonella is a leading cause of foodborne diseases worldwide. The use of antibiotics in food-producing animals may contribute to the development of antimicrobial resistance in nontyphoidal Salmonella. The development of resistance to potent antimicrobials such as fluoroquinolones and extended-spectrum β-lactamases is a significant public health problem. The present study was conducted to examine the occurrence and antimicrobial resistance of Salmonella isolates obtained from food samples. Salmonella was cultured according to ISO 6579:2002 method, and antimicrobial resistance was evaluated with the Kirby-Bauer disk diffusion method. Forty-five Salmonella isolates were recovered, and a high Salmonella prevalence was detected in clams (7 of 20 samples, 35%), chicken (28 of 97 samples, 28.9%) and cow's milk (10 of 80 samples, 12.5%). Salmonella Enteritidis (n = 19) and Salmonella Kentucky (n = 18) were the most prevalent isolates. Multidrug resistance was found in 31.1% of the isolates (14 of 45); 84, 46, 28, and 17% of the isolates were resistant to nalidixic acid, ciprofloxacin, amoxicillin–clavulanic acid, and both ofloxacin and cefotaxime, respectively. The isolates resistant to cefotaxime were screened by PCR for the genes for TEM β-lactamase, extended-spectrum β-lactamases (CTX and OXA), and AmpC β-lactamases (FOX, MOX, DHA, ACC, CIT, and EBC). One Salmonella Kentucky isolate from milk harbored an AmpC gene (FOX), and the same serotype isolated from chicken carried the EBC AmpC determinant. The blaTEM gene was detected in all nonsusceptible isolates. We also screened isolates with reduced fluoroquinolone susceptibility for the presence of transferable plasmid-mediated quinolone resistance determinants. Three qnr genes (qnrB, qnrD, and qnrS) were detected in four isolates (two from milk and two from chicken). To our knowledge, this is the first report of the AmpC FOX and EBC gene families and the qnrD gene within a foodborne pathogen in Tunisia. These findings highlight the emergence of multidrug-resistant Salmonella isolates with decreased susceptibility to fluoroquinolones and third-generation cephalosporins, which are drugs commonly used for the treatment of Salmonella infections. HIGHLIGHTS

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