• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.19-28
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• 2000

There are several main antibacterial susceptibility tests, such as agar dilution method, broth dilution method and disk diffusion technique. Especially, for minimal inhibitory concentration (MIC) test, agar dilution method has been widely used. But that method is so complicated and bothering that it's difficult to treat a large amount of strains. On the other hand, modified broth dilution method(add 1% glucose and 0.018% phenol red as a pH indicator to broth) is fast and easy to perform. Most of all, it can visualize the result by color. The MICs of 22 antibiotics Including penicillins, aminoglycosides, cephalothin, chloramphenicol, lincomycin, ceftiofur, vancomycin and quinolones, erythromycin, colistin. sul-fadimethoxine, trimethoprim for arcanobacterium pyogenes 14 strains, actinobacillus pleuropneu-moniae 41 strains and pasteurella multocida 37 strains, which were collected from porcine during 1996 ∼ 1999, were determined by modified broth dilution method. Actinobacillus pleuropneumoniae was highly susceptible to all kinds of quinolones such as ciprofloxacin, enrofloxacin and norfloxacin and to all aminoglycosides, like gentamicin, apramycin, kanamycin and ampicillin, cephalothin and ceftiofur. But It was quite resistant to solfadimethoxin, colistin and vancomycin. Pasteurella multocida was found to have high susceptibility to ampicillin, cephalothin, chlorampenicol and gentamicin but had mid-degree susceptibility to other aminoglycosides. In addition, it was susceptible to norfloxacin and nalidixic acid, but not to newer fluoroquinolone like ciprofloxacin and enrofloxacin and it was resistant to colistin and kanamycin. Arcanobacterium pyogenes was highly susceptible to most of quinolones such as cipoofloxacin, enrofloxacin and norfloxacin and gentamicin and penicillin G. But it also obtained high resistance against the early quinolone, nalidixic acid and aminoglycosides such as amikacin, apramycin and kanamycin and erythromycin, chlorampenicol, tetracyclin and vancomycin.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.61-69
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• 2000

Thirty-one dairy cow from two farm(more than 500,000 cells/ml of bulk milk) in Kyongbuk northern province were selected because of their high somatic cell(more than 500,000 cells/ml of milk In individual cow). Each cow received. staphylococcus aureus vaccine(Labac Staph) and immunostimulant(Ultracon) by intramuscular injection to be repeated every fifteen days for S times. The present study was investigated variation of somatic cell after administration of Labac Staph and Ultracon, and antibiotics resistance of isolated staphylococcus spp from milk in selected cow. The results obtained through the survey were summarized as follows ; 1. Ten dairy cow was injected in A farm. Chronic mastitic two cow after 2rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, ,3rd, 4th and 5th administration were 41.4%, 35.6%, 56.4%, 65.4% and 36.7%, respectively. Twenty-one cow was injected in B farm. Chronic mastitic five cow after ,3rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, 3rd, 4th and 5th administration were 36.9%, 59.9%, 24.5%, 62.6% and 78.4%, respectively. 2. In A farm, isolated staphylococcus spp were identified as S hyicus 2 strains(11.8%), coagulase negative staphylococcus 15 stains(89.2%) and S epidermidis 6strain(35.3%). In B farm, isolated staphylococcus spp were identified as S aureus 19 strains(55.98%) and coagulase negative staphylococcus 15 strains (44.2%). 3. In A fm, antibiotics resistant rate of isolated staphylococcus spp was high at ampicillin, penicillin and kanamycin, and middle at neomycin, streptomycin and erythromycin. in B farm, antibiotics resistant rate was moderate at ampicillin, penicillin, gentamicin, ka-namycin, neomycin, streptomycin, erythromycin and tetracycline, and coagulase negative staphylococcus spp was moderate at streptomycin.

• Korean Journal of Food Science and Technology
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• v.50 no.6
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• pp.581-586
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• 2018

Enterococcus spp. have been considered major indicator organisms for antibiotic resistance due to their ability to easily acquire and to harbor antibiotic resistance. In this study, Enterococcus spp. were isolated from 174 retail fresh-cut products (fresh vegetable salads, microgreens, and sprouts) in Korea. Among the 20 Enterococcus isolates obtained, 18 (90.0%) were Enterococcus faecalis and 2 (10.0%) were Enterococcus faecium. The patterns of antibiotic resistance against nine antimicrobials were analyzed. Most of the isolates (85.0%) were resistant to quinupristin/dalfopristin, 40.0% and 50.0% of the isolates showed intermediate resistance to two critically important antimicrobials for human medicine, ciprofloxacin and erythromycin, respectively. Vancomycin-resistant enterococci were not detected in this study. Given the importance of antimicrobial resistance of enterococci in food safety as well as in public health, our results regarding the occurrence (level of contamination) and antimicrobial resistance of Enterococcus spp. could provide useful information that aids the risk analysis of antibiotic resistance.

• The Journal of the Korean Society for Microbiology
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• v.17 no.1
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• pp.43-47
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• 1982

C. fetus suhsp. jejuni has been reported to be an important enteric pathogen in many parts of the world. Although the infection has been reported in Korea, the incidence is not known. In this study the results of stool culture during the period of August 1981 to July 1982 at Yonsei Medical Center was analyzed and the following results were obtained. 1. C. fetus subsp. jejuni was isolated from 0.8% of stool specimens. The isolation rate was lower than that of salmonella(3.3%) and shigella(7.1%). The isolation was most frequent in June and from $\leq$15-year-old patients. 2. All of the isolates from the patients were susceptible to chloramphenicol and erythromycin. It was noteworthy that 4 isolates were resistant to all of the aminoglycosides, i.e., amikacin, gen tamicin, kanamycin and tobramycin. 3. We also isolated C. fetus subsp. jejuni from chicken. When the susceptibility of the isolates was compared to that of the isolates from human the former were less susceptible to erythromycin(34.1%) and tetracycline(38.6%).

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.75-83
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• 2005

The purpose of this study was to investigate the antibiotic resistance pattern of E. coli and Salmonella spp. isolated from chicken feces. One hundred and forty-seven E. coli isolates showed resistance to tetracycline (95.2%), erythromycin (89.2%), ampicillin (70.1%), streptomycin (59.2%), cephalothin (56.5%), sulfamethoxazole/trimethoprim (53.7%), ciprofloxacin (57.1%), enrofloxacin (59.2%) and norfloxacin (57.1%). The multiple resistance was seen in 144 isolates (97.9%) and the rate of five, six and seven drugs resistance pattern were 20.4%, 18.4% and 16.3%, respectively. Also, the multiple resistance of E. coli to twelve drugs were seen in 1 isolates (0.7%). Fourteen Salmonella spp. showed resistance to ampicillin (50.0%), streptomycin (57.1%), erythromycin (64.3%) and tetracycline (57.1%) and the rate of two and three drugs resistance pattern were 4 isolates (28.6%), respectively. The prevalence of resistant organisms in Korea probably reflects lack of proper antibiotic policy resulting in prolonged and indiscriminate use of antimicrobial agents.

• Journal of Microbiology and Biotechnology
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• v.32 no.4
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• pp.458-463
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• 2022

We evaluated the antibiotic susceptibilities, hemolytic activities, and technological properties of 36 Staphylococcus xylosus strains and 49 S. pseudoxylosus strains predominantly isolated from fermented soybean foods from Korea. Most of the strains were sensitive to chloramphenicol, erythromycin, gentamycin, kanamycin, lincomycin, oxacillin, tetracycline, and trimethoprim. However, 23 strains exhibited potential phenotypic acquired resistance to erythromycin, lincomycin, and tetracycline. Based on breakpoint values for staphylococci from the Clinical and Laboratory Standards Institute, >30% of the isolates were resistant to ampicillin and penicillin G, but the population distributions in minimum inhibitory concentration tests were clearly different from those expected for acquired resistance. None of the strains exhibited clear α- or β-hemolytic activity. S. xylosus and S. pseudoxylosus exhibited salt tolerance on agar medium containing 20% and 22% (w/v) NaCl, respectively. S. xylosus and S. pseudoxylosus strains possessed protease and lipase activities, which were affected by the NaCl concentration. Protease activity of S. pseudoxylosus was strain-specific, but lipase activity might be a characteristic of both species. This study confirms the potential of both species for use in high-salt soybean fermentation, but the safety and technological properties of strains must be determined to select suitable starter candidates.

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.195-200
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• 2009

Avian pathogenic Escherichia coli (APEC) is an important bacterial pathogen of chickens and causes colibacillosis such as airsacculitis, perihepatitis, omphalitis, peritonitis, salpingitis, and pericarditis. As the transfer of antibiotic resistance from animal to humans can be possible, surveillance on antibiotic resistance of APEC is very important. A total 34 APEC isolates from diseased chickens during the period from 2007 to 2009 were obtained. The susceptibility of the isolates to 13 antibiotics was determined by disc diffusion assay. Resistance to erythromycin was found in 97.1% of APEC isolated, followed by resistance to tetracycline (85.3%), doxycycline (82.3%), ampicillin (73.5%), sulfisoxazole (67.6%), enrofloxacin (67.6%), ciprofloxacin (64.7%), norfloxacin (61.7%) trimethoprim/sulfamethoxazole (52.9%), gentamycin (26.5%), amoxicillin (8.8%), colistin (5.9%), and amikacin (2.9%). The blaTEM genes were detected in 25 (100%) of the 25 ampicillin-resistant APEC isolates. Among the 29 tetracycline-resistant APEC isolates, tetA and tetB genes were detected in 18 (62.1%) and 9 (31%) isolates, respectively. Twenty six (76.5%) isolates were multiresistant to at least 6 antibiotics and seven (20.1%) isolates were multiresistant to at least 10 antibiotics. This results indicated that multiple antibiotic-resistant APEC is widespread in chicken flocks in Korea.

• Korean Journal of Veterinary Research
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• v.30 no.1
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• pp.51-57
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• 1990

In order to know the prevalence of S. hyicus subsp hyicus in pigs, attempts were made to isolate the organism from 549 healthy adult pigs, 277 healthy suckling piglets and 17 piglets with exudative epidermitis from April 1988 to January 1989 in Chinju, Korea. Also determined was antibiotic susceptibility of the isolates. Isolation rates of S. hyicus subsp. hyicus from adult pigs and suekling piglets were 27.0% and 53.1%, respectively. The organism was isolated predominantly from abdomen (10.9%) of adult pigs and external ear (31.6%) of suckling piglets. Isolation rates of the organism from piglets of different age group were in order of prevalence of 1(82.1%), 3(74.0%), 2(54.7%), 4(52.9%), 5(15.2%) and 6(5.7%) post-natal weeks. All of 489 isolates were sensitive to gentamicin, kanamycin and cephalexin but 23.7~79.6% of the strains were resistant to erythromycin, penicillin G and tetracycline. The 49.2% of these resistant strains exhibited multiple drug resistance. The drug resistant patterns most frequently encountered were PG TC EM(10.7%) in triple pattern, PG TC(23.0%) in double pattern and TC(44.4%) in single pattern.

• Food Science of Animal Resources
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• v.37 no.5
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• pp.670-681
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• 2017

The aim of this study was to isolate enterococci in Sucuk, a traditional Turkish dry-fermented sausage and to analyze isolates for their biodiversity, antibiotic resistance patterns and the presence of some antibiotic resistance genes. A total of 60 enterococci strains were isolated from 20 sucuk samples manufactured without using a starter culture and they were identified as E. faecium (73.3%), E. faecalis (11.7%), E. hirae (8.3%), E. durans (3.3%), E. mundtii (1.7%) and E. thailandicus (1.7%). Most of the strains were found resistant to rifampin (51.67%) followed by ciprofloxacin (38.33%), nitrofurantoin (33.33%) and erythromycin (21.67%). All strains were found susceptible to ampicillin. Only E. faecium FYE4 and FYE60 strains displayed susceptibility to all antibiotics. Other strains showed different resistance patterns to antibiotics. E. faecalis was found more resistant to antibiotics than other species. Most of the strains (61.7%) displayed resistance from between two and eight antibiotics. The ermB, ermC, gyrA, tetM, tetL and vanA genes were detected in some strains. A lack of correlation between genotypic and phenotypic analysis for some strains was detected. The results of this study indicated that Sucuk manufactured without using a starter culture is a reservoir of multiple antibiotic resistant enterococci. Consequently, Sucuk is a potential reservoir for the transmission of antibiotic resistance genes from animals to humans.

• Korean Journal of Veterinary Service
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• v.22 no.2
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• pp.121-128
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• 1999

The present study was conducted to investigate the incidence of pneumonic lesions with special regard to enzootic pneumonia and the microbiology of pneumoic lungs from 544 slaughter pigs during the period from October 1995 to September 1996. The incidence of enzootic pneumonic lesion was 76.3% (41s/s44) and pleurisy was detected from 7.9% of slaughter pigs. Seasonal prevalence of pneumonic lesions in slaughter pigs were in order of prevalence of 82.9% in spring, 76.8% in winter, 74.8% in autumn and 69.0% in summer, respectively. Pasteurella multocida, Streptococcus sp, Str suis, Corynebacterium sp, Actinobacillus pleuropneumoniae, Hemophilus parasuis, and Klebsiella pneumoniae were detected in order of prevalence from 16.9%, 15.9%, 7.5%, 6.0%, 1.4%, 1.0% and 0.5% of 415 pneumonic lungs, respectively. P multocida were susceptible to oxytetracycline, polymyxin-B, streptomycin, and vancomycin, while the majority of them were resistant to amoxicillin, ampicillin, cephalothin, kanamycin, and penicillin-G. Str suis were susceptible to amoxicillin, ampicillin, cephalothin, penicillin-G, although the majority of them were resistant to erythromycin, oxytetracycline, streptomycin, vancomycin. A pleuropneumoniae were susceptible to ampicillin, and cephalothin, but the majority of them were resistant to oxytetracycline.