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A total of 690 pathogenic Escherichia (E.) coli isolates from weaned piglets were examined for antimicrobial resistance phenotypes, resistance genes, and virulence gene profiles. Also, 29 enterotoxigenic E. coli (ETEC) and 35 Shiga-toxin producing E. coli (STEC) isolates were analyzed using multi-locus sequence typing (MLST). Comparisons of the associations between antimicrobial resistance phenotypes, resistance genes, and virulence genes were performed separately by assessing odds ratio (OR). Although majorities of associations were not confirmed however, we found that associations between specific virulence factors-antimicrobial resistance. F18 encoding isolates showed association with resistance to cefazolin (OR = 3.08) and cefoxitin (OR = 3.65), and also with antimicrobial resistance gene mcr-3 (OR = 4.58). There was a high correlation between F4-STb (OR = 13.56), F4-LT (OR = 8.77), F4-EAST-I (OR = 4.97), and F18-Stx2e (OR = 3.83). Most of ETEC (21 of 29, 72.4%) isolates were assigned to ST100, and 20 of 35 STEC isolates (57.1%) were ST1. There were 5 clusters, and each cluster showed specific antimicrobial resistance patterns. Cluster I showed resistance to gentamicin, streptomycin, neomycin, nalidixic acid, ciprofloxacin, norfloxacin, trimethoprim / sulfamethoxazole, and tetracyclines whereas, cluster V showed resistance to ampicillin, amoxicillin / clavulanic acid, cephalothin, cefoxitin, cefazolin, norfloxacin, and colistin. Although there is need to do more experiments to clarify why certain virulence factors showed relationship with antimicrobial resistance, it is clear that there is a significant association between specific virulence genes and antimicrobial resistance in E. coli from weaned piglets with enteric colibacillosis in Korea.

This study aimed to examine the distribution of gastrointestinal parasitic infections in domestic pigs in the Republic of Korea. From May 2020 to October 2021, 364 pig fecal samples were collected from 75 farms in 7 Provinces and microscopically examined. A total of 170 (46.7%) pigs were infected with at least one of the following parasites: Balantioides coli, strongyles, Ascaris suum, Trichuris suis, and coccidia. By parasite species, B. coli, strongyles, A. suum, T. suis, and coccidia oocysts or eggs were detected in 144 (39.6%), 24 (6.6%), 14 (3.8%), 4 (1.1%), and 1 (0.3%) samples, respectively. One hundred fifty-four, 15, and 1 cases showed single, double, and triple infections, respectively. Of the swine fecal samples from 75 farms, 69 specimens (92.0%) were infected with 1 or more parasites. All surveyed farms across the country exhibited a positive rate of over 30%, among which the highest positive rate was 65.0% in Chungcheongnam-do, and Jeollabuk-do was followed by 61.9%. Winter showed a statistically lower prevalence than other seasons. This study showed that gastrointestinal parasites are prevalent in pigs in Korea, although the diversity of parasites is low.

Objective This study aimed to analyse the presence of mcr genes and virulence genes in Escherichia coli (E. coli) isolates from diarrhoeic piglets between 2007–2016 in Korea. Methods A total of 364 E. coli isolates were obtained from diarrhoeic weaned piglets between 2007–2016. Minimum inhibitory concentrationss were determined according to the Clinical and Laboratory Standards Institute (CLSI). DNA samples were tested for the presence of mcr-1, mcr-2 and mcr-3 genes. Furthermore, multiplex PCR was used to detect toxin, fimbrial and non-fimbrial adhesin genes. Results It was found that 2.5% (nine of 364) of the isolates carried the mcr genes. Four isolates carried the mcr-1 gene and eight isolates had the mcr-3 gene. Three isolates carried both mcr-1 and mcr-3 genes; the mcr-2 gene was not found. All isolates carrying mcr genes were multidrug-resistant. F18 (77.8%, seven of nine) and Stx2e (44.4%, four of nine) were frequently detected in E. coli carrying the mcr gene. Conclusions In conclusion, it would appear that the most prevalent mcr gene of E. coli from diarrhoeic weaned piglets in Korea was mcr-3. It is believed that this is the first report of two plasmid-mediated colistin resistance genes – mcr-1 and mcr-3 – coexisting in the same isolates (0258, 0491, 0516) from piglets with diarrhoea in Korea. Those mcr–positive isolates showed multidrug resistance and the majority of those encoded Stx2e and F18. This indicates the risk of inefficient treatment for oedema disease in weaned piglets.

Balantioides coli is a zoonotic protozoan parasite whose main reservoir is pigs. Recent studies have shown that B. coli variant A but not B has zoonotic potential. While B. coli infection has been reported in different animals and countries, the prevalence of the zoonotic variant is limited due to a lack of molecular information. Therefore, this study investigated the prevalence of B. coli in domestic pigs in Korea and assessed its zoonotic potential. A total of 188 pig fecal samples were collected from slaughterhouses in Korea. B. coli was identified by microscopy and molecular methods. B. coli was identified in 79 (42.9%) and 174 (94.6%) samples by microscopy and polymerase chain reaction (PCR), respectively. This study also developed a PCR-restriction fragment length polymorphism (PCR-RFLP) method to differentiate B. coli variant A from B without sequence analysis. Using this method, 62 (33.7%) and 160 (87.0%) samples were positive for variants A and B, respectively, and 48 (26.1%) samples were co-infected with both variants. Sequence and phylogenetic analyses showed a high genetic diversity of B. coli in pigs in Korea. To our knowledge, this is the first study to develop a method to differentiate B. coli variants A and B without sequence analysis and to assess the molecular epidemiology of B. coli in pigs. Continuous monitoring of zoonotic B. coli in pigs should be performed as pigs are the main source of human balantidiasis.

Simple Summary Balantioides coli is a protozoan parasite that can infect humans, and its main reservoir is pigs. Recent studies suggested that one of B. coli variants, named variant A, has zoonotic potential. Previous studies have reported B. coli infection in pigs in different countries; however, the prevalence of the zoonotic variant is limited due to a lack of molecular information. In this study, we developed a molecular technique-based method that could differentiate B. coli variant A from B without sequence analysis. Using the method, 174/188 (94.6%) pig fecal samples collected in domestic pigs in Korea were positive for B. coli, and of the samples, 62 (33.7%) were the zoonotic variant. To our knowledge, this is the first study to develop a method to differentiate B. coli variants A and B without sequence analysis and to assess the molecular epidemiology of B. coli in pigs. Abstract Balantioides coli is a zoonotic protozoan parasite whose main reservoir is pigs. Recent studies have shown that B. coli variant A but not B has zoonotic potential. While B. coli infection has been reported in different animals and countries, the prevalence of the zoonotic variant is limited due to a lack of molecular information. Therefore, this study investigated the prevalence of B. coli in domestic pigs in Korea and assessed its zoonotic potential. A total of 188 pig fecal samples were collected from slaughterhouses in Korea. B. coli was identified by microscopy and molecular methods. B. coli was identified in 79 (42.9%) and 174 (94.6%) samples by microscopy and polymerase chain reaction (PCR), respectively. This study also developed a PCR-restriction fragment length polymorphism (PCR-RFLP) method to differentiate B. coli variant A from B without sequence analysis. Using this method, 62 (33.7%) and 160 (87.0%) samples were positive for variants A and B, respectively, and 48 (26.1%) samples were co-infected with both variants. Sequence and phylogenetic analyses showed a high genetic diversity of B. coli in pigs in Korea. To our knowledge, this is the first study to develop a method to differentiate B. coli variants A and B without sequence analysis and to assess the molecular epidemiology of B. coli in pigs. Continuous monitoring of zoonotic B. coli in pigs should be performed as pigs are the main source of human balantidiasis.

Salmonella enterica serotype Choleraesuis causes swine paratyphoid, with clinical findings of enterocolitis and septicemia. However, the clinicopathological features of S. Choleraesuis infections in pigs have not been reported in Korea. We describe the pathological findings of two weaned pigs with S. Choleraesuis infections, presenting with diarrhea, cough, and sudden death. Pathological examination indicated severe necrotic colitis in pig 1 and septicemic lesions in pig 2. Multidrug-resistant S. Choleraesuis was isolated from the pigs’ lungs and intestinal contents. Further research is required for the surveillance of S. Choleraesuis infections in pigs and the virulence estimation in the S. Choleraesuis isolates.

Foot-and-mouth disease (FMD) is a highly contagious and economically devastating disease affecting cloven-hoofed livestock worldwide. FMD virus (FMDV) type A is one of the most common causes of FMD outbreaks among the seven FMDV serotypes, and its serological diagnosis is therefore important to confirm FMDV type A infection and to determine FMD vaccine efficacy. Here, we generated monoclonal antibodies (mAbs) specific to FMDV type A via hybridoma systems using an inactivated FMDV type A (A22/Iraq/1964) and found 4 monoclones (#29, #106, #108, and #109) with high binding reactivity to FMDV type A among 594 primary clones. In particular, the #106 mAb had a higher binding reactivity to the inactivated FMDV type A than the other mAbs and a commercial mAb. Moreover, the #106 mAb showed no cross-reactivity to inactivated FMDV type South African territories 1, 2, and 3, and low reactivity to inactivated FMDV type O (O1 Manisa). Importantly, the solid-phase competitive ELISA (SPCE) using horseradish peroxidase (HRP)-conjugated #106 mAb detected FMDV type A-specific Abs in sera from FMD type A-vaccinated cattle more effectively than a commercial SPCE. These results suggest that the newly developed FMDV type A-specific mAb might be useful for diagnostic approaches for detecting Abs against FMDV type A.

The purpose of this study was to investigate the seroprevalence of antibodies against severe fever with thrombocytopenia syndrome virus (SFTSV) in shelter dogs in the Republic of Korea (ROK) using an indirect immunofluorescence assay and virus neutralization test. Sera were collected from 426 dogs in 12 animal shelters throughout the ROK from March 2016 to November 2016. Overall, 59 of 426 (13.9%) samples were seropositive for antibodies against SFTSV. A significant difference was observed in accordance with the sampling region (p

Streptococcus suis is an important pig pathogen with potential for human transmission. The serotype distributions and phenotypic characteristics vary over time and among regions; however, little is known about the characteristics of S. suis isolates in Korea. In this study, 240 S. suis isolates collected from pigs in Korea in 2009-2010 were serotyped by coagglutination tests, subsequently screened for three virulence-associated genes (mrp, epf and sly) and tested for antimicrobial susceptibility. As for 80 isolates, the serotypes of which were relevant to human infections, clonal complexes (CCs) were further identified by PCR. Serotype 3 was the most prevalent (15.8%), followed by serotype 2 (15.0%), with geographical variation for each serotype. Overall, 55.4% of the isolates carried mrp, whereas only 3.8% carried epf. CC25 was the most prevalent (41.3%) and was related to serotypes 2 and 9. The isolates showed higher susceptibility to ampicillin (93.4%) and ceftiofur (90.8%) than to the other antimicrobial agents tested. The highest resistance rate was observed to tetracycline (98.0%), followed by erythromycin (88.8%). In addition, the resistance to certain antimicrobials was significantly associated, in part, with virulence-associated genes or serotypes. Therefore, continuous characterization of S. suis is essential for the benefit of veterinary and human medicine.

Q fever is a zoonosis caused by Coxiella burnetii, an obligate intracellular Gram-negative bacterium. Q fever is usually subclinical, but is occasionally associated with abortion in ruminants. Two cases of abortion, one in a goat and the other in a cow, were reported to the Animal and Plant Quarantine Agency for diagnostic testing. Histologically, suppurative placentitis was apparent in both cases and more severe in the goat than in the cow. C. burnetii antigens were detected by polymerase chain reaction of DNA from various tissue extracts and antibodies were detected in the sera in both cases. To our knowledge, this is the first report of bovine and caprine abortion caused by C. burnetii in South Korea.

9) Abstract: A 26-month-old male mixed-breed dog of Korean origin was subjected to necropsy following death after a history of decreased appetite and weight loss. Necropsy revealed generalized lymphadenopathy and splenomegaly. Histopathological examination of samples from the spleen, mandibular lymph nodes, liver, kidney, and large intestine showed granulomas with numerous macrophages containing intracytoplasmic Leishmania amastigotes. Transmission electron microscopy revealed Leishmania amastigotes in the macrophage cytoplasm. All tissues with granulomas were positive for Leishmania spp, which was confirmed to be Leishmania infantum by conventional polymerase chain reaction (PCR), real-time PCR, and in situ hybridization. To our knowledge, this is the second case of canine visceral leishmaniasis in Korea.

Brachyspira (B.) hyodysenteriae is a causative agent of swine dysentery that is responsible for death and economic losses in the pig industry. It is imperative that clinical samples be delivered fresh for accurate diagnosis. The viability and DNA detection of B. hyodysenteriae using lab-made (phosphate buffered saline and modified tryptic soy broth) or commercial transport media (C, D, and E) were compared by culturing and real-time PCR at 4 o C or room temperature (RT), respectively. B. hyodysenteriae grown in D (Anaerobe Systems, USA) and E (Starplex Scientific, Canada) media was viable for 4 days at 4 o C and RT. However, B. hyodysenteriae in A, B, and C (culture swab; BD Biosciences, USA) media were not recovered after 2 days at RT. Ct values for real-time PCR at 4 o C and RT ranged from 27.2 ± 2.1 (C) to 29.6 ± 0.5 (B), and 28.0 ± 0.9 (E) to 30.2 ± 1.5 (B), respectively. Considering the field conditions, it is important that transport media is used for specimen isolation and PCR to obtain an accurate diagnosis of swine dysentery.

This study was conducted to assess the seroprevalence and clinical relevance of Corynebacterium pseudotuberculosis, which is the causative agent of caseous lymphadenitis (CLA), in native Korean goats (Capra hircus coreanae). A total of 466 native Korean goats from 40 herds (11 to 12 samples per herd) were randomly selected throughout the nation and evaluated by direct palpation, bacterial isolation, ELISA, and PCR. In serological examinations, 267 (57.3 %) of the goats tested were positive against C. pseudotuberculosis. When seroprevalence was analyzed according to age, region, and season, statistically significant differences were observed in relation to all three parameters (P

Streptococcus suis is an important pig pathogen with potential for human transmission. The serotype distributions and phenotypic characteristics vary over time and among regions; however, little is known about the characteristics of S. suis isolates in Korea. In this study, 240 S. suis isolates collected from pigs in Korea in 2009–2010 were serotyped by coagglutination tests, subsequently screened for three virulence-associated genes (mrp, epf and sly) and tested for antimicrobial susceptibility. As for 80 isolates, the serotypes of which were relevant to human infections, clonal complexes (CCs) were further identified by PCR. Serotype 3 was the most prevalent (15.8%), followed by serotype 2 (15.0%), with geographical variation for each serotype. Overall, 55.4% of the isolates carried mrp, whereas only 3.8% carried epf. CC25 was the most prevalent (41.3%) and was related to serotypes 2 and 9. The isolates showed higher susceptibility to ampicillin (93.4%) and ceftiofur (90.8%) than to the other antimicrobial agents tested. The highest resistance rate was observed to tetracycline (98.0%), followed by erythromycin (88.8%). In addition, the resistance to certain antimicrobials was significantly associated, in part, with virulence-associated genes or serotypes. Therefore, continuous characterization of S. suis is essential for the benefit of veterinary and human medicine.

Severe fever with thrombocytopenia syndrome is a tick-borne infectious disease. The present study investigated the prevalence of severe fever with thrombocytopenia syndrome virus (SFTSV) in shelter dogs and cats in the Republic of Korea (ROK). Blood samples were collected from 426 dogs and 215 cats in animal shelters throughout the ROK in 2016. Of the tested samples, one (0.2%) dog and one (0.5%) cat were positive for SFTSV. Phylogenetic analysis of the sequences obtained in the present study showed that the viruses belonged to the J3 clade, which is considered the dominant clade in the ROK. This study reports the first molecular detection of SFTSV in shelter dogs and cats in the ROK.

A 6-year-old Thoroughbred gelding was euthanized after a 2-month period of abnormal neurological signs, such as circling left in his pen and hitting his head and body against the wall. After the horse was euthanized on the farm, a half of the brain and whole blood were submitted for diagnostic tests. Histopathological examination of the brain revealed granulomatous and eosinophilic meningoencephalitis with numerous intralesional nematodes, predominantly affecting the cerebrum. Multifocal malacic foci were scattered in the brain parenchyma. The intralesional parasites were identified as Halicephalobus gingivalis by morphological features and PCR testing. To the best of our knowledge, this is the first report of meningoencephalitis caused by H. gingivalis in the horse in Korea.

To diagnose colibacillosis, detection of O-serogroups and virulence genes has been recommended worldwide. The prevalence of virulence factors can fluctuate over time. The objectives of this study were to determine the prevalence of O-serogroups, virulence genes, and F18 subtypes among pathogenic Escherichia coli isolated from weaned piglets with diarrhea in Korea. Between 2008 and 2016, 362 E. coli were isolated from weaned piglets with diarrhea. Hemolysis was determined in blood agar, and O-serogroups were identified using the slide agglutination technique. The genes for the toxins and fimbriae were amplified by polymerase chain reaction (PCR). Real-time PCR was conducted to discriminate between F18 subtypes. Although the most prevalent serogroup was O149 (11.3%) in the last 9 years, O139 (19.1%) became the most prevalent in recent years (2015–2016). The most predominant pathotype was enterotoxigenic E. coli (61.3%). The frequencies of Shiga-like toxin-producing E. coli (STEC) (23.4%), O139 (19.1%), Stx2e (35.1%), and F18ab (48.7%) increased over the most recent years. Although enterotoxigenic E. coli was the most predominant pathotype, the frequencies of O139, Stx2e, STEC, and F18ab have increased in recent years. These results demonstrate that there have been temporal changes in the predominant O-serogroups and virulence genes over the last decade in Korea. These findings can be practicable for use in epidemiology and control measures for enteric colibacillosis in Korean piggeries.

Bacteria are frequently contaminated during the collection and processing procedures of boar semen. Of the contaminants, Stenotrophomonas (S.) maltophilia is a Gram-negative bacterium that is widely distributed in a variety of habitats. Although PCR assays have been developed for the detection of S. maltophilia, they cross-react with some species of Xanthomonas. In this study, we designed a primer set for the detection of S. maltophilia in order to target the chiA (GenBank accession no. NC_010943) gene. The specific PCR products were amplified from S. maltophilia only, not from other tested strains that are frequently found in semen. The detection limit of the PCR was 1.5×10³ CFU/ml with pure-cultured S. maltophilia and 1.5×10⁴ CFU/ml with S. maltophilia spiked in semen. Twenty-six (5.9%) S. maltophilia were isolated from 440 semen samples. The PCR results exhibited 98.9% agreement with a comparison of S. maltophilia isolation. Also, the sensitivity and specificity of the PCR were 100% and 98.7%, respectively. In the antimicrobial susceptibility test, S. maltophilia isolates were highly susceptible to enrofloxacin and florfenicol, while the majority of them were resistant to amoxicillin/clavulanic acid, apramycin, ceftiofur, penicillin, and spectinomycin. These results indicated that the PCR using the chiA gene was proven to be reliable and effective for the detection of S. maltophilia with high levels of sensitivity and specificity.

A total of 47 extended-spectrum-cephalosporin-resistant Escherichia coli strains isolated from stray dogs in 2006 and 2007 in the Republic of Korea were investigated using molecular methods. Extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase phenotypes were identified in 12 and 23 E. coli isolates, respectively. All 12 ESBL-producing isolates carried bla CTX-M genes. The most common CTX-M types were CTX-M-14 ( n = 5) and CTX-M-24 ( n = 3). Isolates producing CTX-M-3, CTX-M-55, CTX-M-27, and CTX-M-65 were also identified. Twenty-one of 23 AmpC β-lactamase-producing isolates were found to carry bla CMY-2 genes. TEM-1 was associated with CTX-M and CMY-2 β-lactamases in 4 and 15 isolates, respectively. In addition to bla TEM-1 , two isolates carried bla DHA-1 , and one of them cocarried bla CMY-2 . Both CTX-M and CMY-2 genes were located on large (40 to 170 kb) conjugative plasmids that contained the insertion sequence IS Ecp1 upstream of the bla genes. Only in the case of CTX-M genes was there an IS 903 sequence downstream of the gene. The spread of ESBLs and AmpC β-lactamases occurred via both horizontal gene transfer, accounting for much of the CTX-M gene dissemination, and clonal spread, accounting for CMY-2 gene dissemination. The horizontal dissemination of bla CTX-M and bla CMY-2 genes was mediated by IncF and IncI1-Iγ plasmids, respectively. The clonal spread of bla CMY-2 was driven mainly by E. coli strains of virulent phylogroup D lineage ST648. To our knowledge, this is the first report of bla DHA-1 in E. coli strains isolated from companion animals. This study also represents the first report of CMY-2 β-lactamase-producing E. coli isolates from dogs in the Republic of Korea.

Salmonella are causative agents of gastroenteritis and systemic disease in animals. The invA gene was selectedas a target sequence of loop-mediated isothermal amplification (LAMP) assay for diagnosis of Salmonella infection.The detection limits for broth dilution, spiked feces and enrichment were 10 4 , 10 5 and 10 2 CFUs/mL, respectively.The LAMP assay developed in the present study may be a reliable method for detection of Salmonella spp. in pig feces.Keywords : detection limit, invA, loop-mediated isothermal amplification assay, Salmonella Salmonella (S.) are gram-negative bacilli belong to thefamily of Enterobacteriaceae and comprise a number ofclosely related serotypes, many of which are responsible forvarious illness and death in animals [5, 8]. Although most ofthe Salmonella cause gastrointestinal disorder, some Serovarsuch as Cholerasuis, Abortusequi, Gallinarum produce sys-temic diseases [3]. It is important that the identification ofcausative agent is simple and rapid. A variety of methodssuch as isolation and PCR have been applied for salmonello-sis in animal and human beings. Although isolation of agentsis golden method for diagnosis of the disease, it is laboriousand time consuming. Thus, molecular diagnostics such asPCR have been applied to detect Salmonella spp. in fecesand pork [1]. However, there are shortcomings such as carry-over contaminations and non-specific reactions. Recently,loop-mediated isothermal amplification (LAMP) has beendeveloped and used as an alternative for molecular diagnosis[13]. LAMP is a nucleic acid amplification technique thatrelies on an auto-cycling strand displacement DNA synthesisunder isothermal condition [10, 11, 12, 13]. Although thereare some reports for inspections such as eggs and pork [14,19], there are few reports for developing LAMP for diagnos-tic purpose. Therefore, LAMP assay was developed for ampli-fying invA gene to detect the Salmonella spp. and evaluatedfor the detection limit and specificity. Nineteen strains containing 6 Salmonella spp. (Cholerasuis,Derby, Enteritidis, Montevideo, Schwarzenground, Typhimu-rium) and 13 non-Salmonella spp. (Acinetobacter haemolyticusATCC17906, Acinetobacter johnsonii ATCC17909, Acineto-bacter junii ATCC17098, Alcaligenes xylosoxydans ATCC15173,Burkholderia cepacia ATCC25416, Comamonas testosteroniATCC11996, Enterobacter cloacae ATCC13047, Escheri-chia coli ATCC25922, Kocuria rosea ATCC186, Micrococ-cus luteus ATCC4698, Ochrobactrum anthropi ATCC49188,Serratia marcescens ATCC13880, Stenotrophomonas malto-philia ATCC13637) were used. All strains of Salmonellawere from field isolates and serogrouped by O and H anti-body (Becton, Dickson and Company, USA) except S. Chol-eraesuis (ATCC 10708). The primer sequence is shown inTable 1. Salmonella invasion protein gene (invA) was tar-geted for the LAMP assay. Each primer was designed usingPrimerExplorer V3 software (Eiken Chemical, Japan). Theprimers consisted of forward outer (F3), backward outer(B3), forward inner (FIP), backward inner (BIP), loop for-ward (LF), and loop backward (LB). The reaction was car-ried out in a 25µL volume containing 15µL of IsothermalMaster Mix (OptiGene, UK), 50µM of the primers FIP andBIP, 25µM of the primers LF and LB, 5µM of the primersF3 and B3 and 2µL of DNA template. The amplified signalwas detected by Genie (OptiGene) under the 63

National Veterinary Research and Quarantine Service, Anyang, 43 0-757, KoreaReceived February 27, 2010/Accepted April 5, 2010Plasmid-mediated quinolone resistance (PMQR) determinants have been contributed to quinolone re-sistance of gram-negative bacteria worldwide. However, little data on the prevalence of these determi-nants in bacteria from animals are available in Korea. In this study, the prevalence of PMQR genes was investigated with E. coli originating from diseased animals. Among 55 E. coli tested, 11 showed PMQR genes by PCR. The most prevalent genotype was qepA (14.5%), followed by aac(6′)-Ib-cr (7.3%) and qnrS (1.8%). Interestingly, two isolates with PMQR genes did not show quinolone resistance in this study. The isolates exhibited higher fluoroquinolone resistance in aac(6′)-Ib-cr in combination with qnrS or qepA compared with aac(6′)-Ib-cr only. In a conjugal transfer test, PMQR genes were trans-ferred from donor to recipient. Keywords : Plasmid-mediated quinolone resistance (PMQR), qnrS, aac(6′)-Ib-cr, qepA

Background and aims: Canine adenovirus type 2 (CAV-2) infection is typically diagnosed histopathologically since intranuclear inclusion bodies (IN/IBs) are demonstrable in the infected lung. However, it is sometimes difficult to identify IN/IBs, particularly in autolyzed tissues or samples from both early and late stages of infection, and other methods were presently developed. Methods: Stray dog samples were evaluated by histopathology, polymerase chain reaction (PCR), and immunohistochemistry (IHC) to investigate the status of the CAV-2 infection on the stray dogs in Korea. Histologic tests were performed, and dogs with pneumonic lungs were further evaluated by IHC and PCR. Results: Pathognomonic IN/IBs were identified in 3 of 213 lungs; CAV-2 PCR was positive for 27 of 213 pneumonic lungs. A total of 7 of 27 CAV-2 PCR-positive lungs were IHC-positive. No PCR-negative lung was IHC-positive. Positive results were primarily detected in the IN/IBs of the bronchial epithelial cells, macrophages, and very rarely in the cytoplasm of bronchial epithelial cells. Conclusions: IHC was a more reliable diagnostic method than conventional pathologic methods in the present study, and suggests that IHC should be routinely used in the diagnosis of CAV-2 infection. Further, PCR alone may not be adequate for CAV-2 diagnosis.

Ten farrow-finish farms participated in this seromonitoring that was conducted to investigate the porcine brucellosis situation in Korea. In total, eight (80.0%) of the 10 farms and 139 (24.0%) of 578 pigs tested showed a positive response in the Rose Bengal test (RBT). Seroprevalence levels were determined using RBT according to age; 35 (14.6%) of 239 piglets, 36 (31.3%) of 115 growing pigs, and 68 (30.4%) of 224 finishing pigs and sows were positive, respectively. All positive samples in RBT were tested with the tube agglutination test (TAT) and competitive ELISA (C-ELISA), simultaneously. Although 48 samples came up positive in the TAT, all samples tested with C-ELISA were negative. Among 26 rectal swab samples from the TAT positive-pigs, Yersinia enterocolitica O:9 was isolated from seven samples (26.9%). Therefore, we speculated that the positive reaction of RBT and TAT in this study might be induced by the serologically cross-reacting bacteria with Brucella abortus.

A total of 628 Escherichia coli isolates recovered from 877 intestinal samples of stray pet dogs (n = 565) and hospitalized pet dogs (n = 312) in Korea were analyzed for resistance to 15 antimicrobial agents. Most common resistance observed in E. coli isolated from both groups of dogs was to tetracycline (52.4-53.6%), streptomycin (35.8-41.7%), ampicillin (32.9-47.1%), nalidixic acid (21.6-37.4%), and trimethoprim/sulfamethoxazole (19.7-36.4%). Resistance to chloramphenicol, gentamicin, and ciprofloxacin was observed in 19.4% (17.1-24.3%), 18% (16.1-21.8%), and 16.1% (13.5-21.4%) of the isolates, respectively. No E. coli isolated from hospitalized dogs showed resistance to imipenem and cefepime, whereas three (0.7%) isolates from stray dogs were resistant to cefepime. Some of the isolates from both groups showed resistance to cefotaxime (2.4-3.9%) and amikacin (0.5-1.5%). In general, the frequency of resistance tended to be higher in isolates from hospitalized dogs than isolates from stray dogs against most antimicrobials tested. Around 39% (162/422) and 27% (55/206) of E. coli isolates from stray dogs and hospitalized dogs were susceptible to all antimicrobials tested, respectively. Multiresistance (or = 3 subclasses of antimicrobials) was observed in 32% and 48% of E. coli isolates from stray dogs and hospitalized dogs, respectively. More attention should be paid to the use of antimicrobials and the occurrence of antimicrobial resistance in companion animals.

In spite of intensive surveillance programs for the control of HPAI, an outbreak of highly pathogenic avian influenza (HPAI) H5N1 in Korea in April 2008 caused serious damage to poultry farms, as did previous outbreaks in 2003/2004 and 2006/2007. Six viruses were selected from the Korean 2008 isolates for genetic analysis, and all eight gene segments from each of the influenza viruses were sequenced. A phylogenetic analysis showed that all of the viruses were of the same virus type and that the hemagglutinin (HA) gene was clustered with that of clade 2.3.2 viruses. However, the internal and neuraminidase (NA) genes were closely related to those of the clade 2.3.4 viruses (recent human and bird isolates from Southeast Asia).

Clostridium difficile is an important cause of enteric disease in humans and animals. The prevalence of C. difficile infection is increasing, and the bacterium is frequently found in meat products, suggesting the possibility of animal-to-human transmission. Therefore, food animals must be assessed for their role as reservoirs of C. difficile. In this study, C. difficile was isolated from 2 (0.3%) of 659 slaughtered pigs in Korea. Both isolates were characterized as ribotype 078 and were multidrug resistant. The low occurrence suggests only a limited risk of C. difficile transmission from porcine food products; however, C. difficile ribotype 078 is an important pathogen in both pigs and humans, and further studies are necessary to investigate the occurrence of C. difficile in retail meats and other food animals.

A 2-day-old goat died suddenly after the onset of severe diarrhea. No specific gross lesions were observed except for a remarkably thin intestinal wall and watery intestinal contents. Histopathological analysis revealed large numbers of Gram-positive bacilli layered upon the intestinal epithelia of the small intestine. Heavy growth of only Clostridium perfringens type E, and no detection of the other enteric pathogens in the small intestine, suggests that C. perfringens type E contributed to the death of this kid. To our knowledge, this is the first isolation of C. perfringens type E from a goat with diarrhea.

Digital photographs of 16 pork chops were taken and modified images to give 16 treatments: two levels of each of fat cover, color, marbling and drip. Consumers(n = 1,014) were randomly selected and a questionnaire asking for socio-demographic information was completed. Each consumer was asked to select preferred type from 16 treatments and this selection was repeated eight times. There were significant differences in pork selection among age, sex and occupation groups only except income levels. Pork preference choices were different in meat color, fat cover and drip depending on age group. Student consumers aging from 18 to 24 years preferred pork chop having darker color, thinner fat cover and more drip when compared to the other groups(p < 0.05). Male preferred pork having darker and more drip than female(p < 0.05). Marital status had a effect on the preference in meat color and drip. The consumers had different choice in color, fat cover and drip depending on occupation(p < 0.05). This results can provide a fundamental information for industries or processors to develop or produce pork that satisfy each target consumer group in the future.

A 2-year-old Pekinese dog was diagnosed with hepatic yersiniosis. Grossly, white-to-yellow nodules consisting of degenerated inflammatory cells, cell debris, and bacterial clumps were scattered throughout the liver. Histopathologically, suppurative and necrotizing hepatitis was apparent. Yersinia enterocolitica biotype 4, serotype O3 (4:O3) was identified and confirmed in the liver immunohistochemically, using a monoclonal antibody. The virulence genes ystA and ail were detected, but the isolate was negative for autoagglutination and calcium-dependent growth. To confirm systemic yersiniosis in animals, it is imperative that the organism(s) be identified because the hepatic lesions are similar to those of Y. pseudotuberculosis and other diseases, including plague, which is also a zoonotic pathogen.

Clinical grape poisoning in two dogs (a 1.6-year-old male Shih Tzu and a 5-year-old female Yorkshire Terrier) was described in the present study. Clinical signs included decreased urine output in the Shih Tzu and ataxia in the Yorkshire Terrier after grape ingestion. The Shih Tzu died 5 days post-grape ingestion, while the Yorkshire Terrier died 3 days post-grape ingestion. Erythematous serosae and mucosae, multifocal red small intestinal foci, and blood and grape seeds were identified in the intestinal lumen. Brownish-yellow crystals were bilaterally identified in the renal pelvis. The primary histological findings were acute tubular necrosis of the proximal convoluted tubules, severe necrosis, and mineralization in the renal cortical tubules. Blood urea nitrogen, creatinine, and alanine aminotransferase were increased in the dogs. Many Korean veterinary clinicians have suspected clinical grape poisoning. However, to our knowledge, grape poisoning has not been identified by pathologic and clinicopathologic basis until this writing in Korea. Education and knowledge about the risks of grape poisoning is necessary for the prevention of accidental exposures.

The occurrence of Q fever in native Korean goats (Capra hircus coreanae) was investigated for the first time in the country using ELISA and PCR. A total of 597 blood samples were collected from goats belonging to five different provinces of Korea. To detect Coxiella burnetii, sera were separated from the whole blood and analysed by ELISA; DNA was extracted directly from the whole blood and analysed by PCR. Overall, 114 (19.1%, 95% C.I.=16.1-22.4) and 57 goats (9.5%, 95% C.I.=7.5-12.2) tested positive for C. burnetii in the ELISA- and PCR-based screening, respectively, while 18 goats (3.0%, 95% C.I.=1.9-4.7) tested positive in both the assays. There was a significant difference between the number of ELISA- and PCR-positive goats (P

To estimate the prevalence of Escherichia coli with potential pathogenicity in cattle farm in South Korea, a total of 290 E. coli isolates were isolated from cattle farms over a period of 2 years in South Korea. These were examined for phenotypic and genotypic characteristics including antimicrobial susceptibility, serotype, and gene profiles of virulence and antimicrobial resistance. The most dominant virulence gene was f17 (26.2%), followed by stx2 (15.9%), ehxA (11.0%), stx1 (8.3%), eae (5.2%), and sta (4.1%). Some shiga-toxin producing E. coli isolates possessed eae (15.9%). All isolates except for one showed resistance to one or more antimicrobials, with 152 isolates exhibiting multidrug-resistance. The most prevalent resistance phenotype detected was streptomycin (63.1%), followed by tetracycline (54.5%), neomycin (40.3%), cephalothin (32.8%), amoxicillin (30.0%), ampicillin (29.7%), and sulphamethoxazole/trimethoprim (16.6%). The associated resistance determinants detected were strA-strB (39.0%), tet(E) (80.0%), tet(A) (27.6%), aac(3)-IV (33.1%), aphA1 (21.4%), bla TEM (23.8%), and sul2 (22.1%). When investigated by O serotyping and PFGE molecular subtyping, the high degree of diversity was exhibited in E. coli isolates. These results suggest that E. coli isolates from South Korean cattle farms are significantly diverse in terms of virulence and antimicrobial resistance. In conclusion, the gastroinstestinal flora of cattle could be a significant reservoir of diverse virulence and antimicrobial resistance determinants, which is potentially hazardous to public health.

An outbreak of fatal hemorrhagic pneumonia with 70~90% morbidity and 50% mortality occurred in an animal shelter in Yangju, Gyeonggi Province, Korea. Clinically, the affected dogs showed severe respiratory distress within 48 h after arriving in the shelter. The dead were found mainly with nasal bleeding and hematemesis. At necropsy, hemothorax and hemorrhagic pneumonia along with severe pulmonary consolidation was observed, though histopathological analysis showed mainly hemorrhagic bronchopneumonia. Lymphoid depletion was inconsistently seen in the spleen, tonsil and bronchial lymph node. Gram-positive colonies were shown in blood vessels or parenchyma of cerebrum, lung, liver, spleen, and kidney. Also, Streptococcus (S.) equi subsp. zooepidemicus was isolated from the various organs in which the bacterium was microscopically and histologically detected. In addition, approximately 0.9 Kb specific amplicon, antiphagocytic factor H binding protein, was amplified in the bacterial isolates. In this study, we reported an outbreak of canine hemorrhagic bronchopneumonia caused by S. equi subsp. zooepidemicus in an animal shelter in Yangju, Korea.