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1.
Acta Vet Hung ; 68(2): 123-129, 2020 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-33055304

RESUMEN

Bovine tuberculosis (bTB) is a common zoonosis prevalent in many countries with grave economic consequences. Most developed and developing countries have implemented the test-and-slaughter policy to protect public health and reduce economic losses in the cattle industry. The official diagnosis of bTB is based on assays dependent on cell-mediated immunity (CMI). CMI-based diagnosis demonstrates diagnostic incapability at late stages of infection, which could be overcome by diagnosis based on humoral immunity (HI). Therefore, there is an urgent need to identify and define the B cell antigenome of Mycobacterium bovis. In this study, the B cell antigenome of culture filtrate proteins (CFP) was defined by mass spectrometry-based proteomics technology. Four spots were detected on 2-dimensional gel electrophoresis (2-DE) against M. bovis-positive serum in an immunoblotting experiment. Twenty-one proteins were identified in four spots by proteomic tools, such as Mb2900, Mb2898, Mb0448, Mb3834c, Mb1918c, Mb0134c, Mb0358 and Mb1868c, which are known B cell antigens, including 13 new proteins, i.e. Mb3751, Mb2006c, Mb3276c, Mb2244, Mb1164c, Mb2553c, Mb2946c, Mb1849c, Mb1511c, Mb1034c, Mb2616c, Mb0854c and Mb2267. These new proteins identified by 2-DE and immunoblotting were the B cell antigens used in developing serological diagnostic methods based on HI to bTB.


Asunto(s)
Linfocitos B/inmunología , Proteínas Bacterianas/análisis , Genoma Bacteriano , Mycobacterium bovis/inmunología , Proteoma , Mycobacterium bovis/genética , Proteómica
2.
J Vet Med Sci ; 82(11): 1631-1638, 2020 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-33055466

RESUMEN

Bovine tuberculosis (bTB) is a zoonosis caused by Mycobacterium bovis. Test-and-cull protocols and gross pathological examinations of abattoir animals as well as milk pasteurization have been implemented to prevent the spread of tuberculosis from animals to humans worldwide. Despite the importance of precise and rapid diagnostic tests, conventional methods including intradermal skin tests and γ-interferon assays are limited by the high rate of false-negative results for cattle in the late infectious stage and due to laborious and time-consuming procedures. Therefore, antibody detection methods such as enzyme-linked immunosorbent assay (ELISA) are urgently needed to supplement the established approaches and expand the diagnostic window. This study was conducted to develop a bTB ELISA by evaluating recombinant and native proteins and various assay parameters. We produced recombinant MPB70 and SahH (M70S) and a native 20-kDa protein (20K) and optimized the ELISA protocol. The 20K ELISA showed 94.4% sensitivity and 98.2% specificity with an optimal sample-to-positive ratio cut-off of 0.531. The sensitivity and specificity of M70S ELISA were 94.4% and 97.3%, respectively, with an optimal sample-to-negative ratio cut-off of 1.696. Both assays showed acceptable diagnostic efficiency and could be used for bTB diagnosis in combination with established methods for herd screening and to expand the diagnostic window.


Asunto(s)
Enfermedades de los Bovinos , Mycobacterium bovis , Tuberculosis Bovina , Tuberculosis , Animales , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Sensibilidad y Especificidad , Tuberculosis/veterinaria , Tuberculosis Bovina/diagnóstico
3.
Vet Microbiol ; 205: 62-65, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28622864

RESUMEN

Twenty field isolates of Avibacterium paragallinarum were obtained from chickens in South Korea during 2011-2015. The isolates were identified by a HPG-2 PCR assay specific for A. paragallinarum and by biochemical tests. Growth requirements, Page serovars, carbohydrate fermentation patterns, and antimicrobial susceptibility were also examined. Most isolates (16/20) showed the typical requirement for nicotinamide adenine dinucleotide (NAD) and an enriched CO2 atmosphere for growth. One isolate needed increased levels of NAD and serum for good growth. Three isolates showed NAD-independent growth on blood agar under aerobic conditions. In terms of carbohydrate fermentation patterns, three biochemical biovars were recognized; these varied with respect to acid production from maltose and D-xylose. The 16 typical NAD-dependent isolates were serovar A while the variants, both NAD-independent isolates and the isolate with increased NAD dependency were non-typeable. All isolates were sensitive to amoxicillin-clavulanic acid, ceftiofur, gentamicin, and spectinomycin. High rates of resistance, including intermediate resistance, to lincomycin (100%), cloxacillin (75%), and erythromycin (70%) were observed. The four variant strains (the three NAD-independent isolates and the isolate showing unusual growth requirements) were more resistant to antibiotics than the typical NAD-dependent strains. The finding of NAD-independent forms of A. paragallinarum extends the known distribution of this form, previously only reported in South Africa, Mexico and Peru. There is clearly a need for increased caution in the diagnosis and, possibly, the control of infectious coryza.


Asunto(s)
Pollos/microbiología , Gammaproteobacteria/aislamiento & purificación , NAD/metabolismo , Enfermedades de las Aves de Corral/microbiología , Animales , Antibacterianos , Gammaproteobacteria/crecimiento & desarrollo , Gammaproteobacteria/inmunología , Gammaproteobacteria/metabolismo , Enfermedades de las Aves de Corral/epidemiología , República de Corea/epidemiología , Serogrupo
4.
J Microbiol Biotechnol ; 27(4): 868, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28468442

RESUMEN

This erratum is being published to correct the errors of the words in the section of introduction and title. The words of 't324'(left column, line 20, 21; right column, line 4, 14) in page 799 and title should be corrected as 't034'.

5.
J Dairy Sci ; 100(5): 3463-3469, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28318579

RESUMEN

In this study, we aimed to assess trends in antimicrobial resistance and to investigate the characteristics of extended-spectrum ß-lactamase (ESBL)-producing isolates from bovine mastitic milk from 2012 to 2015. A total of 374 Escherichia coli isolates were analyzed (154 in 2012, 113 in 2013, 76 in 2014, and 31 in 2015). No consistent trends in antimicrobial resistance of E. coli isolates occurred during the 4-yr period. The most frequently observed resistance was tetracycline (23.3%), followed by streptomycin (17.1%), ampicillin (16.6%), neomycin (11.8%), and trimethoprim/sulfamethoxazole (11.2%). Multidrug resistance was observed in 15.5% of isolates. Among these isolates, 15 (4.0%) carried one or more blaCTX-M and AmpC ESBL genes from 11 different farms, including blaCTX-M-15 at 4 farms, blaCTX-M-3 at 2 farms, blaCTX-M-1 at 3 farms, and blaCMY-2 at 3 farms. This study is the first report of blaCTX-M-3-producing E. coli in dairy milk. Transfer of ESBL was observed in 3 blaCTX-M-3-producing isolates, 1 blaCTX-M-1-producing isolate, and all 3 blaCMY-2-producing isolates. Almost all blaCTX-M-15 and blaCTX-M-1 genes possessed an insertion sequence, ISECP1, upstream of the blaCTX-M gene. Identical pulsed-field gel electrophoresis profiles were also observed in blaCTX-M-producing E. coli from the same farm. These results suggested that ESBL might spread by both clonal and horizontal spread in dairy farms in South Korea. Although no significant changes occurred in the antimicrobial resistance of E. coli during the 4-yr study period, the resistance rates and presence of ESBL were high compared with those in other countries. Thus, these findings suggest the importance of control measures for E. coli, particularly ESBL-producing bacteria, on dairy farms to reduce treatment failure and transmission to humans.


Asunto(s)
Escherichia coli/aislamiento & purificación , beta-Lactamasas , Animales , Antiinfecciosos/uso terapéutico , Bovinos , Infecciones por Escherichia coli/veterinaria , Humanos , Leche/microbiología , Plásmidos
6.
Vet Microbiol ; 201: 252-256, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28284617

RESUMEN

Altogether 7720 Enterococcus faecalis and 3939 E. faecium isolated from food animals and animal carcasses during 2003-2014 in Korea were investigated to determine if linezolid-resistant (LR) enterococci (≥8µg/ml) are present. Overall, 12 E. faecalis and 27 E. faecium recovered from chickens (n=32), pigs (n=6), and cattle (n=1) were resistant to linezolid and were further characterized using molecular methods Most LR isolates were also resistant to chloramphenicol (97.44%) and florfenicol (92.31%). Molecular analysis showed no mutations in the 23S ribosomal RNA and in the ribosomal protein L3. The optrA gene was found in 89.74% of the LR enterococci, including 12 E. faecalis and 23 E. faecium isolates. Among them, 30 optrA-positive isolates co-carried phenicol exporter gene fexA. Seven LR E. faecium isolates had Asn130Lys mutations in the ribosomal protein L4, of which six also carried optrA gene. None of the isolates carried the mutliresistance gene cfr. Transfer of optrA gene was observed in 16 of the 35 optrA-positive isolates by conjugation. Pulsed-field gel electrophoresis demonstrated that the vast majority of Enterococcus strains carrying optrA gene were genetically heterogeneous. Multi-locus sequence typing revealed eight novel Sequence types among E. faecalis and E. faecium strains. To our knowledge, this is the first report of optrA gene in isolates from cattle and animal carcasses. This is also the first report of optrA gene in Korea. Active surveillance of optrA in enterococci is urgently warranted.


Asunto(s)
Antibacterianos/farmacología , Pollos/microbiología , Farmacorresistencia Bacteriana/genética , Enterococcus/efectos de los fármacos , Microbiología de Alimentos , Infecciones por Bacterias Grampositivas/veterinaria , Animales , Técnicas de Tipificación Bacteriana/veterinaria , Bovinos , Cloranfenicol/farmacología , Electroforesis en Gel de Campo Pulsado/veterinaria , Enterococcus/genética , Enterococcus/aislamiento & purificación , Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/aislamiento & purificación , Heces/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Linezolid/farmacología , Tipificación de Secuencias Multilocus/veterinaria , Mutación , Oxazolidinonas/farmacología , República de Corea , Porcinos , Tianfenicol/análogos & derivados , Tianfenicol/farmacología
7.
J Vet Med Sci ; 78(12): 1791-1795, 2017 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-27593510

RESUMEN

Resistance to antimicrobials was measured in 73 isolates of Campylobacter jejuni (C. jejuni) and 121 isolates of Campylobacter coli (C. coli) from chicken and swine feces and carcasses in Korea. Both bacterial species showed the highest resistance to (fluoro) quinolones (ciprofloxacin and nalidixic acid) out of the nine antimicrobials tested. Erythromycin resistance was much higher in C. coli (19.0%, 23/121) than in C. jejuni (6.8%, 5/73). The mutation in the 23S rRNA gene was primarily responsible for macrolide resistance in Campylobacter isolates. Several amino acid substitutions in the L4 and L22 ribosomal proteins may play a role in the mechanism of resistance, but the role requires further evaluation. A total of eight virulence genes were detected in 28 erythromycin-resistant Campylobacter isolates. All C. jejuni isolates carried more than four such genes, while C. coli isolates carried fewer than three such genes. The high rate of resistance highlights the need to employ more prudent use of critically important antimicrobials, such as fluoroquinolones and macrolides, in swine and poultry production, and to more carefully monitor antimicrobial resistance in Campylobacter isolates in food animals.


Asunto(s)
Antibacterianos/farmacología , Campylobacter coli/efectos de los fármacos , Campylobacter jejuni/efectos de los fármacos , Pollos/microbiología , Eritromicina/farmacología , Heces/microbiología , Macrólidos/farmacología , Carne/microbiología , Porcinos/microbiología , Factores de Virulencia/genética , Animales , Campylobacter coli/genética , Campylobacter coli/aislamiento & purificación , Campylobacter jejuni/genética , Campylobacter jejuni/aislamiento & purificación , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Mutación Puntual , ARN Ribosómico 23S/genética , República de Corea
8.
J Microbiol ; 55(1): 13-20, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28035601

RESUMEN

Thirty-nine human isolates of Campylobacter jejuni obtained from a national university hospital during 2007-2010 and 38 chicken isolates of C. jejuni were collected from poultry farms during 2009-2010 in South Korea were used in this study. Campylobacter genomic species and virulence-associated genes were identified by PCR. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were performed to compare their genetic relationships. All isolates were highly resistant to ciprofloxacin, nalidixic acid, and tetracycline. Of all isolates tested, over 94% contained seven virulence associated genes (flaA, cadF, racR, dnaJ, cdtA, cdtB, and cdtC). All isolates were classified into 39 types by PFGE clustering with 90% similarity. Some chicken isolates were incorporated into some PFGE types of human isolates. MLST analysis for the 39 human isolates and 38 chicken isolates resulted in 14 and 23 sequence types (STs), respectively, of which 10 STs were new. STs overlapped in both chicken and human isolates included ST-21, ST-48, ST-50, ST-51, and ST-354, of which ST-21 was the predominant ST in both human and chicken isolates. Through combined analysis of PFGE types and STs, three chicken isolates were clonally related to the three human isolates associated with food poisoning (VII-ST-48, XXII-ST-354, and XXVIII-ST-51). They were derived from geographically same or distinct districts. Remarkably, clonal spread of food poisoning pathogens between animals and humans was confirmed by population genetic analysis. Consequently, contamination of campylobacters with quinolone resistance and potential virulence genes in poultry production and consumption may increase the risk of infections in humans.


Asunto(s)
Infecciones por Campylobacter/epidemiología , Infecciones por Campylobacter/microbiología , Campylobacter jejuni/genética , Campylobacter jejuni/aislamiento & purificación , Pollos/microbiología , Animales , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Infecciones por Campylobacter/transmisión , Campylobacter jejuni/clasificación , Campylobacter jejuni/efectos de los fármacos , Ciprofloxacina/farmacología , ADN Bacteriano/genética , Farmacorresistencia Bacteriana Múltiple , Electroforesis en Gel de Campo Pulsado , Enfermedades Transmitidas por los Alimentos/microbiología , Genotipo , Humanos , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa , República de Corea/epidemiología , Tetraciclina/farmacología , Virulencia/genética
10.
Avian Dis ; 60(2): 535-9, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27309301

RESUMEN

Highly pathogenic avian influenza (HPAI) virus of the H5N8 subtype was isolated from a young ostrich in South Korea in March 2014. Clinical signs characterized by anorexia, depression, and signs of nervousness were observed. The isolated A/ostrich/Korea/H829/2014 (H5N8) virus had a cleavage site motif containing multiple basic amino acids, typical of HPAI virus. The phylogenetic tree of the hemagglutinin gene of the H5 HPAI virus showed that this ostrich H5N8 virus belongs to clade 2.3.4.4 viruses together with H5N8 strains isolated from ducks and wild birds in South Korea in 2014. Pathologically, redness of pancreas, enlargement and hemorrhage of spleen, friability of brain, and hydropericardium were prominently found. Histologic legions were observed in pancreas, spleen, liver, lung, heart, and brain, and influenza A nucleoproteins were detected in the same organs by immunohistochemistry. Other ostriches farmed together in open camps were not infected with HPAI virus based on the serologic and virologic tests. The findings indicate that ostriches are susceptible to H5N8 HPAI virus, but this virus does not spread efficiently among ratites.


Asunto(s)
Subtipo H5N8 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/diagnóstico , Struthioniformes , Animales , Proteínas Aviares/genética , Hemaglutininas/genética , Subtipo H5N8 del Virus de la Influenza A/clasificación , Subtipo H5N8 del Virus de la Influenza A/genética , Gripe Aviar/transmisión , Gripe Aviar/virología , Filogenia , República de Corea , Análisis de Secuencia de ADN/veterinaria
11.
Genome Announc ; 4(1)2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26950323

RESUMEN

We report the draft genome sequence of a novel livestock-associated t2247-ST692-III methicillin-resistant Staphylococcus aureus strain designated K12S0375, which was isolated from a chicken carcass in South Korea. The K12S0375 strain contains uncommon genes, including antimicrobial resistance genes (tetL and tetS) and leukotoxin (lukED), and the genomic distance indicates a single lineage in a genome-based phylogenetic tree compared with 459 S. aureus genome sequences. This genome sequence will contribute to understanding epidemiological and genomic features of the ST692 lineage, including antimicrobial resistance and virulence genes.

12.
J Microbiol Biotechnol ; 26(4): 799-805, 2016 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-26699744

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA), the major causative agent of nosocomial infection, has also been reported from non-human sources. A sequence type (ST) 541 MRSA isolate designated K12PJN53 was isolated from a healthy pig in 2012. The genome of K12PJN53 consists of 44 contiguous sequences (contigs), totalling 2,880,108 bases with 32.88% GC content. Among the annotated contigs, 14, 17, and 18 contained genes related to antimicrobial resistance, adherence, and toxin genes, respectively. The genomic distance of strain K12PJN53 was close to the ST398 strains. This is the first report of the draft genome sequence of a novel livestock-associated MRSA ST541 strain.


Asunto(s)
Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Análisis de Secuencia de ADN , Porcinos/microbiología , Animales , Antibacterianos/farmacología , Adhesión Bacteriana/genética , Toxinas Bacterianas/genética , Secuencia de Bases , Farmacorresistencia Bacteriana/genética , Genómica , Staphylococcus aureus Resistente a Meticilina/fisiología
13.
Virol J ; 12: 177, 2015 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-26502988

RESUMEN

BACKGROUND: Virus-like particle (VLP) technology is considered one of the most promising approaches in animal vaccines, due to the intrinsic immunogenic properties as well as high safety profile of VLPs. In this study, we developed a VLP vaccine against infectious bursal disease virus (IBDV), which causes morbidity and mortality in chickens, by expressing a baculovirus in insect cells. METHODS: To improve the self-proteolytic processing of precursor polyprotein (PP), we constructed a recombinant baculovirus transfer vector that co-expresses PP and the VP4 protease gene of IBDV. RESULTS: Expression and VLP assembly of recombinant proteins and antigenicity of the VLP were examined by Western blotting, ELISA, and transmission electron microscopy. In animal experiments, vaccination with the recombinant VLP induced strong and uniform humoral immunity and provided complete protection against challenge with very virulent (vv) IBDV in SPF chickens (n = 12). As determined by the bursa of Fabricius (BF)/body weight (B/BW) ratio, the protection against post-challenge bursal atrophy was significantly higher (P < 0.001) in VLP-vaccinated birds than in non-vaccinated controls. CONCLUSIONS: Since the protective efficacy of the VLP vaccine was comparable to that of a commercially available inactivated vaccine, the recombinant VLP merits further investigation as an alternative means of protection against vvIBD.


Asunto(s)
Infecciones por Birnaviridae/veterinaria , Virus de la Enfermedad Infecciosa de la Bolsa/inmunología , Enfermedades de las Aves de Corral/prevención & control , Vacunas de Partículas Similares a Virus/inmunología , Vacunas Virales/inmunología , Animales , Anticuerpos Antivirales/sangre , Baculoviridae/genética , Infecciones por Birnaviridae/patología , Infecciones por Birnaviridae/prevención & control , Western Blotting , Bolsa de Fabricio/patología , Línea Celular , Pollos , Ensayo de Inmunoadsorción Enzimática , Vectores Genéticos , Virus de la Enfermedad Infecciosa de la Bolsa/genética , Virus de la Enfermedad Infecciosa de la Bolsa/metabolismo , Insectos , Microscopía Electrónica de Transmisión , Poliproteínas , Enfermedades de las Aves de Corral/patología , Multimerización de Proteína , Resultado del Tratamiento , Vacunas de Partículas Similares a Virus/administración & dosificación , Vacunas de Partículas Similares a Virus/genética , Vacunas de Partículas Similares a Virus/ultraestructura , Proteínas Estructurales Virales/genética , Proteínas Estructurales Virales/metabolismo , Vacunas Virales/administración & dosificación , Vacunas Virales/genética , Virosomas/genética , Virosomas/metabolismo , Virosomas/ultraestructura
14.
Foodborne Pathog Dis ; 12(9): 766-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26192872

RESUMEN

Salmonella enterica subspecies enterica serovar 4,[5],12:i:-, a monophasic variant of Salmonella Typhimurium, has emerged as one of the most common serotypes related to human salmonellosis. In this study, the 22 isolates of S. 4,[5],12:i:- from food animals were identified by a specific multiplex polymerase chain reaction between 2009 and 2012. The isolation rate of S. 4,[5],12:i:- accounted for 1.7% (22/1271) of Salmonella spp. isolates from food animal origins: more specifically, 7.6% (18/235) from pigs and 0.6% (4/686) from chickens. The predominant S. 4,[5],12:i:- isolates in Korea belonged to phage type DT193 (12/22) with ampicillin-streptomycin-sulfonamide-tetracycline (ASSuT) resistance pattern (9/22). The XbaI-pulsed-field gel electrophoresis (PFGE) analysis revealed 11 different pulsotypes, and the major X-1 pattern was shared by 8 isolates. The isolates belonging to pattern X-1 were further subdivided into three BlnI-PFGE patterns and four variable-number tandem-repeat analysis (MLVA) allele combinations. The combining of MLVA and PFGE data could be valuable in characterizing highly clonal strains and discriminating their epidemiological relationship.


Asunto(s)
Microbiología de Alimentos , Carne/microbiología , Salmonella typhimurium/genética , Animales , Antibacterianos/inmunología , Pollos , Farmacorresistencia Bacteriana/genética , Electroforesis en Gel de Campo Pulsado , Reacción en Cadena de la Polimerasa , Aves de Corral/microbiología , República de Corea , Salmonella typhimurium/inmunología , Salmonella typhimurium/aislamiento & purificación , Porcinos
15.
Vet Microbiol ; 178(1-2): 119-24, 2015 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-25982261

RESUMEN

This study compared the prevalence of Salmonella spp. and their antimicrobial susceptibilities in pigs from conventional and organic farms during 2012-2013 in Korea and characterized them by molecular methods. Altogether, 100 nontyphoid Salmonella were isolated: 47 from 1324 pigs (3.5%) from conventional farms and 53 from 641 pigs (8.3%) from organic farms. The most frequent serovar was Typhimurium (49%) followed by Panama (24%), 1,4,[5],12:i:- (5%), and Virchow (5%). Overall, the isolates were most often resistant to tetracycline (75%) followed by ampicillin (66%), streptomycin (57%), and gentamicin (44%). The prevalence of antimicrobial resistance, multi-drug resistance phenotype, and resistance to tetracycline, ampicillin, and gentamicin were significantly higher in swine Salmonella from conventional farms than those from organic farms. The most common resistance pattern was ampicillin-gentamicin-tetracycline (n=16). All eight ceftiofur-resistant Salmonella identified produced CTX-M-15. Overall, decreased susceptibility to ciprofloxacin was observed in 39 isolates. Among them, a single isolate was positive for qnrS1 gene. An insertion sequence ISEcp1 was detected upstream of blaCTX-M gene in all isolates. The spread of blaCTX-M-15 gene was attributed to combination of clonal expansion and horizontal dissemination mediated by IncHI2 plasmid. Multilocus variable number of tandem repeats analysis demonstrated clonal dissemination of S. Typhimurium and S. 1,4,[5],12:i:- strains in pigs. To our knowledge, this is the first report of blaCTX-M-15 gene in S. Virchow from pigs and qnrS1 gene in S. Rissen from animals. This study also reports the first occurrence of Salmonella serovar 1,4,[5],12:i:- from Korea and CTX-M-15 producing Salmonella from pigs in Korea.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple/genética , Salmonelosis Animal/epidemiología , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/microbiología , Animales , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Agricultura Orgánica/normas , Plásmidos/genética , Prevalencia , República de Corea/epidemiología , Serogrupo , Especificidad de la Especie , Porcinos
16.
J Clin Microbiol ; 53(7): 2332-6, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25903569

RESUMEN

Characterization of 227 Streptococcus suis strains isolated from pigs during 2010 to 2013 showed high levels of resistance to clindamycin (95.6%), tilmicosin (94.7%), tylosin (93.8%), oxytetracycline (89.4%), chlortetracycline (86.8%), tiamulin (72.7%), neomycin (70.0%), enrofloxacin (56.4%), penicillin (56.4%), ceftiofur (55.9%), and gentamicin (55.1%). Resistance to tetracyclines, macrolides, aminoglycosides, and fluoroquinolone was attributed to the tet gene, erm(B), erm(C), mph(C), and mef(A) and/or mef(E) genes, aph(3')-IIIa and aac(6')-Ie-aph(2″)-Ia genes, and single point mutations in the quinolone resistance-determining region of ParC and GyrA, respectively.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana , Genes Bacterianos , Streptococcus suis/efectos de los fármacos , Streptococcus suis/genética , Animales , Proteínas Bacterianas/genética , Pruebas de Sensibilidad Microbiana , Análisis de Secuencia de ADN , Infecciones Estreptocócicas/veterinaria , Streptococcus suis/aislamiento & purificación , Porcinos
17.
Foodborne Pathog Dis ; 12(4): 327-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25786036

RESUMEN

This study was undertaken to screen methicillin-resistant Staphylococcus aureus (MRSA) in animal carcasses and slaughterhouse workers and characterize MRSA isolates identified during 2010-2012 in Korea. A total of 830 (16.4%) S. aureus and 65 (1.3%) MRSA were isolated from 9669 carcass samples. MRSA was more frequently detected in chicken carcasses (1.2%) than in cattle (0.3%) and pig carcasses (0.6%). The prevalence of MRSA in workers was 6.9% (4/58) in chicken slaughterhouse workers, but no MRSA was detected in pig and cattle slaughterhouse workers (0/41). Two different lineages of MRSA were identified (i.e., human-associated type [ST5, ST59, and ST72] and livestock-associated [LA] type [ST398, ST541, and ST692]); only LA MRSA was observed in chicken carcasses, whereas both types were found in cattle and pig carcasses and workers. All human-associated MRSA isolates carried enterotoxin and/or leukotoxin genes, whereas LA MRSA types did not carry these genes, except ST692 type. However, all LA MRSA isolates were multiresistant, whereas human-associated types were susceptible or resistant to fewer than two antimicrobials except ST5. Furthermore, one or more resistance genes were attributed for resistance to aminoglycosides (aac(6')-Ie-aph(2″), ant(4')-Ia, and aph(3')-IIIa), tetracycline [tet(K), tet(L), tet(M), and tet(S)], macrolide-lincosamide-streptogramin B (ermA, ermB, ermC, and ermT), lincosamide [lnu(B)], phenicol-lincosamide-oxazolidinone-pleuromutilin-streptogramin A (cfr), chloramphenicol (fexA), and fusidic acid [fus(C)]. To our knowledge, this is the first report of tet(S) gene in MRSA isolates and first detection of a unique (ST692) type of MRSA in occupational workers. Detection of new types of human-associated and LA MRSA with multiple resistance and virulence genes in food animal products constitutes a potential threat to public health.


Asunto(s)
Ganado/microbiología , Carne/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/microbiología , Mataderos , Animales , Antibacterianos/farmacología , Bovinos , Pollos , Gentamicinas/farmacología , Humanos , Kanamicina/farmacología , Staphylococcus aureus Resistente a Meticilina/clasificación , Pruebas de Sensibilidad Microbiana , República de Corea , Porcinos , Virulencia
18.
Vet Microbiol ; 176(3-4): 274-81, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25676210

RESUMEN

Identifying sources of Mycobacterium bovis transmission would be essential for establishing effective control programs of bovine tuberculosis (TB), a major zoonosis threatening human health worldwide. As an effort to determine the extent of M. bovis transmission among dairy and beef cattle and deer populations, a mycobacterial interspersed repetitive units (MIRU)-variable-number tandem repeats (VNTR) typing method was employed for analysis of 131 M. bovis isolates from 59 Holstein dairy cattle, 39 Korean beef cattle, and 33 deer. Of 31 MIRU-VNTR markers, 15 showed allelic diversity. The most discriminatory locus for M. bovis isolates was VNTR 3336 (h=0.59) followed by QUB 26, MIRU 31, VNTR 2401, and VNTR 3171 which showed high discriminatory power (h=0.43). The combined VNTR loci had an allelic diversity of 0.83. On the basis of the VNTR profiles of 30 VNTR loci, 24 genotypes were identified, and two genotypes were highly prevalent among all M. bovis isolates (33.6% and 19.1%, respectively), thus indicating that more than 50% of the isolates shared common molecular characteristics. Six additional genotypes were common in 2 of the 3 animal species, suggesting a wide interspecies transmission of M. bovis. This study thus demonstrates that MIRU-VNTR typing is useful in differentiation of M. bovis isolates and that M. bovis transmission occurs frequently among farmed animal species, highlighting the importance of bovine TB control programs in different animal species which are often raised in the same villages.


Asunto(s)
Enfermedades de los Bovinos/transmisión , Ciervos/microbiología , Repeticiones de Minisatélite/genética , Mycobacterium bovis/clasificación , Tuberculosis Bovina/transmisión , Tuberculosis/transmisión , Alelos , Animales , Técnicas de Tipificación Bacteriana/veterinaria , Bovinos , Enfermedades de los Bovinos/microbiología , Industria Lechera , Femenino , Sitios Genéticos/genética , Genotipo , Masculino , Mycobacterium bovis/genética , Mycobacterium bovis/aislamiento & purificación , República de Corea/epidemiología , Tuberculosis/microbiología , Tuberculosis Bovina/microbiología
19.
Vet Microbiol ; 174(3-4): 456-462, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25458421

RESUMEN

This study was focused on characterization of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli isolates from chickens and CTX-M associated plasmid addiction systems (PASs) in E. coli from animals using molecular methods. In total, E. coli from nine (9.0%) of the 100 chicken samples examined produced CTX-M type ESBL namely CTX-M-14 (n=4), CTX-M-15 (n=4), and CTX-M-1 (n=1). All of them harbored an additional blaTEM-1 gene. Transfer of blaCTX-M gene was observed in eight out of the nine blaCTX-M-positive isolates by conjugation. Plasmid profiling of blaCTX-M-positive transconjugants revealed a high-molecular weight (95-165 kb) plasmid. Pulsed-field gel electrophoresis showed that most CTX-M-producing chicken isolates were genetically diverse. Furthermore, investigation of 92 conjugation-positive E. coli strains carrying blaCTX-M genes from pigs (n=76), chickens (n=8), and dogs (n=8) identified 230 PASs in the parental strains and 118 in their transconjugants. Among them, hok-sok, pemKI, and pndAC were the most frequently represented PASs in both the parental strains and the transconjugants. Moreover, the hok-sok and pemKI systems were strongly associated to IncF plasmids and the pndAC system to IncI1-Iγ plasmids. Our results suggest that the rapid spread of CTX-M genes in E. coli isolates among the animals could be attributed to the presence of multiple PASs in the CTX-M plasmids. To our knowledge, this is the first report of characterization of CTX-M associated PASs in E. coli isolates from pigs, chickens, and dogs. In addition, CTX-M-1 was detected for the first time in Korea.


Asunto(s)
Enfermedades de los Perros/microbiología , Infecciones por Escherichia coli/veterinaria , Escherichia coli/genética , Enfermedades de las Aves de Corral/microbiología , Enfermedades de los Porcinos/microbiología , beta-Lactamasas/genética , Animales , Pollos , Enfermedades de los Perros/epidemiología , Perros , Escherichia coli/enzimología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Plásmidos/genética , Enfermedades de las Aves de Corral/epidemiología , República de Corea/epidemiología , Porcinos , Enfermedades de los Porcinos/epidemiología
20.
J Food Prot ; 77(9): 1481-6, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25198838

RESUMEN

This study compared the antimicrobial susceptibility and prevalence of virulence genes in Salmonella enterica Typhimurium isolated from healthy and diseased pigs in Korea. A total of 456 Salmonella Typhimurium isolated from healthy (n = 238) and diseased (n = 218) pigs between 1998 and 2011 were investigated. In total, 93.4% of the Salmonella Typhimurium isolates were resistant to at least one antimicrobial agent tested. The isolates were most often resistant to tetracycline (85.7%), followed by streptomycin (83.6%), nalidixic acid (67.3%), ampicillin (49.3%), chloramphenicol (42.8%), and gentamicin (37.1%). Moreover, multidrug resistance phenotype and resistance to ampicillin, florfenicol, gentamicin, nalidixic acid, neomycin, streptomycin, and tetracycline were significantly higher (P < 0.01) among Salmonella Typhimurium isolates from the diseased pigs compared with those from the healthy pigs. The most common resistance pattern observed in both groups of isolates was streptomycin-tetracycline. Overall, more than 96% of the isolates tested possessed invA, spiA, msgA, sipB, prgH, spaN, tolC, lpfC, sifA, sitC, and sopB virulence genes. The prevalence of orgA, pagC, and iroN were 50.2, 74.1, and 91.0%, respectively, whereas isolates carrying cdtB (1.5%), pefA (7.0%), and spvB (14.9%) were identified much less frequently. Furthermore, the prevalence of invA, lpfC, orgA, pagC, and iroN was significantly higher (P < 0.01) among the isolates from the diseased pigs than in isolates from the healthy pigs. Our results demonstrated that, among diseased pigs, there was significantly higher resistance to some antimicrobials and greater prevalence of some virulence genes than in healthy pigs, indicating the role these factors play in pathogenesis. Multidrug-resistant Salmonella isolates that carry virulence-associated genes are potentially more dangerous and constitute a public health concern. Thus, continuous surveillance of antimicrobial resistance and virulence characteristics in Salmonella is essential.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Salmonelosis Animal/microbiología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/patogenicidad , Enfermedades de los Porcinos/microbiología , Animales , Pruebas de Sensibilidad Microbiana , República de Corea , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Porcinos , Virulencia
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