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A total of 782 blood and 465 tissue samples from 1,039 wild animals and 127 dairy goats were collected from January 2011 to December 2013 in 10 provinces of South Korea and tested for the presence of brucellosis. The Rose Bengal test revealed that 8.0% (52/650) of the serum samples were seropositive, while 4.2% (33/782) of the serum samples were positive for Brucella antibodies by competitive enzyme-linked immunosorbent assay. Of the 650 sera examined, only 16 (2.5%) were positive by both serological tests. Direct polymerase chain reaction (PCR) assay using B4/B5 primers for Brucella abortus (BCSP31) revealed the prevalence of Brucella to be 26.5% (129/487) in blood samples and 21% (98/465) in tissue samples while, 16S rRNA PCR detected Brucella DNA in 6.8% (33/487) and 2.6% (12/465) in blood and tissue samples, respectively. Of PCR-positive samples, only 6.2% (30/487) of blood samples and 2.4% (11/465) of tissue samples were found to be positive by both BCSP31 and 16S rRNA PCRs. However, Brucella strains were isolated by blood culture from only two out of 487 blood samples (0.4%). This characterization and identification of pathogenic Brucella isolates is the first to clearly indicate that the organisms were Brucella abortus biovar 1. [ABSTRACT FROM AUTHOR]

Multiple-locus variable number of tandem repeats analysis (MLVA) is useful for epidemiological investigations. In this study, MLVA-18 was used to assess the genetic and epidemiological relationships of Brucella canis isolates among a domestic dog and dogs from two breeding farms. MLVA-18 assay showed variation in copy numbers in 6 of the 18 loci. Interestingly, the YJ02-1 strain isolated from the pet dog from Yangju-si showed only one tandem repeat change in Bruce 09 locus as compared with that of NYJ-1 strain isolated from a dog from the Namyangju-si farm. The two strains were shown to have originated from the same source or a closely related strain. [ABSTRACT FROM AUTHOR]

The article presents a study on the prevalence of Brucella infection in wildlife and stray dogs, cats and rodents in farms. The researchers took samples of tissue and blood from these animals and these were tested for Brucella or Brucella-specific antibodies either by isolation, polymerase chain reaction (PCR) and serology. The study reported the prevalence of this infection using serological and molecular methods and the first isolation of Brucella abortus in wild Chinese water deer in South Korea.

The article discusses results of a study that assesses the genotype of 77 Brucella canis isolates from dog breeding farms in South Korea by the multiple-locus VNTR analysis (MLVA) assay. It also compares the epidemiological relationships between foreign and Korean isolates. It observes that Korean Brucella canis isolates have high generic diversity and divided into 30 distinct genotypes. The study notes the usefulness of the MLVA assay to analyze the epidemiological correlation of Brucella canis isolates in pet animals as well as determine the geographic origin by way of genetic pattern comparison with foreign isolates.

The article discusses research on species distribution and patterns of resistance to growth-promoting antimicrobials of the bacteria Enterococcus faecium and Enterococcus faecalis from pigs and chickens in the Republic of Korea. E. faecium and E. faecalis isolates were tested against antimicrobials including penicillin, flavomycin and bacitracin. Penicillin was found to have the strongest antimicrobial activity against both bacteria. A comparison of the prevalence of resistance in both bacteria between Korea and European countries is provided.

A total of 84 extended-spectrum β-lactamase (ESBL)-producing Escherichia coli isolates from cattle, farm workers, and the farm environment isolated from February to September 2008 in the Republic of Korea were investigated. All 84 ESBL-producing isolates carried blaCTX-M genes that belonged to the CTX-M-1 (n = 35) or CTX-M-9 (n = 49) family. The most predominant CTX-M type identified was CTX-M-14 (n = 49), followed by CTX-M-32 (n = 26). The blaCTX-M genes were identified most commonly in E. coli isolates from feces (n = 29), teats (n = 25), and milk (n = 14). A blaCTX-M-14 gene was also detected in an E. coli isolate from a farmer's hand. Transfer of the blaCTX-M gene from 60 blaCTX-M-positive E. coli isolates to the recipient E. coli J53 strain by conjugation was demonstrated. Plasmid isolation from blaCTX-M-positive transconjugants revealed a large (95- to 140-kb) conjugative plasmid. Almost all (82/84) blaCTX-M genes possessed an insertion sequence, ISEcp1, upstream of the blaCTX-M gene. Only in the case of the CTX-M-14 genes was IS903 downstream of the gene. The blaCTX-M genes were associated with seven kinds of addiction systems. Among them, pndAC, hok-sok, and srnBC were the most frequently identified addiction systems in both wild strains and transconjugants. The spread of blaCTX-M genes was attributed to both clonal expansion and horizontal dissemination. Our data suggest that a combination of multiple addiction systems in plasmids carrying blaCTX-M genes could contribute to their maintenance in the host cells. To our knowledge, the blaCTX-M-32 gene has not previously been reported in animal isolates from the Republic of Korea. [ABSTRACT FROM AUTHOR]

Two new primer sets of a 766- and a 344-bp fragment were introduced into the conventional Bruce-ladder PCR assay. This novel multiplex PCR assay rapidly and concisely discriminates Brucella canis and Brucella microti from Brucella suis strains and also may differentiate all of the 10 Brucella species. [ABSTRACT FROM AUTHOR]