• Journal of Veterinary Clinics
• /
• v.11 no.2
• /
• pp.507-516
• /
• 1994

The purposes of this investigations were survey of the occurred bacterial diseases, development of new animal health drug, guidance to formers on the treatment and control methods of diseases. Some series of investigations have been carried out by microbiological, pathological and serological examinations. The results could be summarized as follows. 1. A total of 953 cases of outbreaked swine diseases have been diagnosed in Clinical pathology laboratories, Bayer Vet Res Institute during 8 years (from 1986 to 1993). The high incidence diseases were colibacillosis, pleuropneumonia, streptococcal infection and pasteurellosis in decreasing order. 2. Pleuropneumonia caused by Actinobacillus pleuropneumoniae was the most important respiratory diseases and pasteurellosis by Pasteurella multocide could be confirmed in several cases. 3. Actinobacillus pleuropneumoniae 50 strains were isolated and identified by biochemical and serological tests. In serotyping test, 22 isolated strains were serotype 5, 21 strains as serotype 2, each 2 strains as serotype 3 and 7 by the coagglutination test. 4. Colibacillosis and edema discase caused by Escherichia coli has been the most predominant outbreaked disease in this investigations. The 100 isolates of E coli strains were sensitive to amikacin, colistin, enrofloxacin, gentamycin and trimethoprim -sulfamethoxazole. 5. Swine erysipelas caused by Erysipelothrix rhusiopathiae was confirmed 25 cases as acute septicemic forms. Isolates of E rhusiopathiae were highly sensitive to ampicillin, cephalothin, enrofloxcin, penicillin and tetracycline. 6. The 49 cases of hemorrhagic and necrotic enteritis in piglets were observed and 13 strains of Clostridium perfringens could be isolated and confirmed by biological and serological test. Isolates of Clostridium perfringens type C were highly sensitive to ampicillin, cephalothin, enrofloxacin, penicillin and trimethoprim- sulfamethoxazole. 7. The 14 strains of Streptococcus suis type II could be isolated from meningitis of piplets. 8. Polyserositis caused by Haemophilus parasuis and salmonellosis were observed and confirmed. Also Corynebacterial infections and several parasitosis have been also observed in this investigations.

• Journal of Veterinary Clinics
• /
• v.28 no.2
• /
• pp.254-257
• /
• 2011

A 2-year-old bearded dragon was referred to the Veterinary Medical Center at the College of Veterinary Medicine, Chungbuk National University with reduced activity and anorexia. On fecal examination, over growth of a bacteria and the proliferation of a yeast-like organism were found. The patient diagnosed with enteritis. By using fungal cultures and molecular typing, the yeast was identified as Pichia (P.) burtonii. The bearded dragon was treated with oral ketoconazole and trimethoprim/sulfamethoxazole. After 3 days, the dragon was recovered and fecal examination showed that the yeast had disappeared from the feces. The strain P. burtonii is supposed opportunistic pathogen in bearded dragon with enteritis according to its reports in a human. This report is the first paper about overgrowth of P. burtonii in a bearded dragon.

• Korean Journal of Veterinary Service
• /
• v.33 no.1
• /
• pp.59-66
• /
• 2010

This study was carried out to investigate the characters of Listeria monocytogenes isolated from food, animal feces, dry cattle food, and the environment in Seoul and Kyonggi province during the period from 1998 to 2003. Serotyping of 70 L. monocytogenes isolates was performed according to the manufacturer's instruction. Minimum inhibitory concentrations (MICs) were determined by the microdilution method according to the guidelines of the Clinical and Laboratory Standards Institute. All the isolates were tested against 20 antimicrobial agents. The serotypes of the 70 L. monocytogenes isolates were 1/2c (62.8%), 1/2a (20%) and 1/2b (17.2%). Of the 70 L. monocytogenes isolates, 67.1%, 57.1%, 11.4%, 5.7%, 2.8%, 1.4% and 1.4% were resistant to tetracycline (Te), minocycline (Mi), norfloxacin (Nor), ciprofloxacin (Cip), neomycin (N), chloramphenicol (C) and cephalothin (Cf), respectively. However, all isolates were 100% sensitive to antibiotics such as amikacin, ampicillin, erythromycin, gentamycin, imipenem, kanamycin, ofloxcin, streptomycin, penicillin, trimethoprim, trimethoprim/sulfamethoxazole, tobramycin, and vancomycin. Multiple resistance patterns of the isolates were observed in TeMiNor Cip (1.4%), TeMiNor (7.1%), TeMiCip (2.9%), TeMiN (1.4%) and TeMi (44.3%). The results of this study indicate that many L. monocytogenes isolates are resistant to antimicrobial agents including Te and Mi. The possibility that the isolates could increasingly acquire multiple antimicrobial resistant properties cannot be precluded.

• Korean Journal of Veterinary Service
• /
• v.44 no.3
• /
• pp.133-140
• /
• 2021

This study was aimed to investigate the prevalence and antimicrobial resistance of Pseudomonas spp. isolated from bovine mastitis milk samples. A total of 50 (4.9%) Pseudomonas spp. was isolated from 1,023 samples, those collected between 2018 and 2021, derived from 110 dairy farms. The prevalence of the identified species of Pseudomonas isolates was as follows; P. aeruginosa (70.0%), P. fluorescens (14.0%), P. putida (10.0%), P. fragi (4.0%), and P. chlororaphis (2.0%). Most of somatic cell counts in the quarter milk carrying Pseudomonas spp. were less than 3,000,000 cell/ml (90.0%). The isolates of Pseudomonas spp. showed high susceptibility to cefepime (98.0%), ciprofloxacin (98.0%), ceftazidime (96.0%), and colistin (96.0%). The rate of antibiotic resistance in the isolates was highest to ceftiofur (92.0%), followed by the resistance rate to chloramphenicol (86.0%) and trimethoprim/sulphamethoxazole (80.0%). In addition, there is a remarkable difference in antimicrobial resistance pattern among Pseudomonas species. P. aeruginosa and P. putida showed a similar resistance pattern, whereas P. fluorescens showed exceptionally lower resistance to trimethoprim/sulphamethoxazole and chloramphenicol than that of the other species. This study showed that prevalence of Pseudomonas spp. other than P. aeruginosa were 30.0% in bovine mastitis milk, and the occurrence rate of antibiotic resistance were similar or higher level, compared with the previous reports on the mastitisderived Pseudomonas spp. isolated in Korea.

• Korean Journal of Transplantation
• /
• v.32 no.4
• /
• pp.92-103
• /
• 2018

Background: Currently, trimethoprim-sulfamethoxazole is used for Pneumocystis jirovecii pneumonia (PJP) prophylaxis, but it is associated with frequent adverse effects. This study evaluated the efficacy and safety of the current protocol and proposes an individualized risk-based prophylaxis protocol. Methods: The PJP incidence and risk factors during the first 6 months (early PJP) and afterwards (late PJP) was assessed in renal transplant recipients with (prophylaxis group) and without (no-prophylaxis group) 6-month PJP prophylaxis. Results: In 578 patients, there were 39 cases of PJP during a median follow-up of 51 months. Renal adverse events were encountered frequently during trimethoprim-sulfamethoxazole prophylaxis, leading to premature discontinuation. Patients without the prophylaxis had a significantly higher incidence of early PJP (n=27, 6.6%) compared to patients with the prophylaxis (n=0). The incidence of late PJP was 2.2%, without between-group differences. The factors associated with early PJP were preoperative desensitization and acute rejection within 1 month, whereas late PJP was associated with age, deceased donor transplant, and acute rejection requiring antithymocyte globulin treatment. Conclusions: Based on the simulation results of several risk-based scenarios, the authors recommend universal prophylaxis up to 6 months post-transplant and extended selective prophylaxis in patients aged ${\geq}57$ years and those with a transplant from deceased donors.

• Microbiology and Biotechnology Letters
• /
• v.16 no.5
• /
• pp.413-420
• /
• 1988

The strain capable of growing on minimal medium containing aniline as a sole source of carbon was isolated from activated sludges and identified as Pseudomonas putida biotype A. The characterizations of the strain were determined. The optimum concentration for growth of the strain was 1-20 mM of aniline. No changes of pH were detected during cultivation. Some metabolic products of biodegradation of aniline were detected after cultivation of the strain on 10 mM aniline for 48 hours. The strain showed to be resistant to streptomycin, tetracycline, trimethoprim, and sulfanilamide. The strain was also capable of utilizing other aromatic compounds related to aniline as a sole source of carbon. One plasmid carried by this strain was detected. The properties of some of the mutant strains treated with mitomycin C were also discussed. The results suggest that separate, regulatory enzyme systems capable of degrading aniline may exist in plasmid DNA.

• Journal of Veterinary Clinics
• /
• v.40 no.6
• /
• pp.393-398
• /
• 2023

We identified mastitis-causing pathogens using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) in an organic dairy farm and evaluated the effects of antimicrobial restriction on antimicrobial susceptibility. A total of 43 Holstein cows without any clinical sign of mastitis were used in this study, and 172 quarter milk samples were cultured on blood agar plates for 24 hours at 37℃. Subsequently, bacterial species were identified and antimicrobial susceptibility tests were performed. The subclinical mastitis infection rates in the cows and quarters were 58.1% (25/43) and 25.6% (44/172), respectively. In the species identification, Staphylococcus aureus (40.9%) was the most prominent isolate, followed by S. chromogenes (22.7%), S. epidermis (18.2%), S. simulans (11.4%), S. haemolyticus (2.3%), S. muscae (2.3%), and S. xylosus (2.3%). In the antimicrobial susceptibility test, all isolates were 100% susceptible to 24 of 28 antibiotics, except for benzylpenicillin, cefalotin, cefpodoxime, and trimethoprim/sulfamethoxazole. The resistance rates of S. aureus, S. chromogenes, and S. muscae isolates to trimethoprim/sulfamethoxazole were 27.8%, 10%, and 100%, respectively, and the resistance rates of S. epidermis and S. xylosus to benzylpenicillin were 50% and 100%, respectively. S. chromogenes, S. epidermis, S. simulans, S. haemolyticus, and S. xylosus were resistant to cefalotin and cefpodoxime. In conclusion, restrictions on antimicrobial use for organic dairy farm certification have resulted in a high Staphylococcus spp. infection rate. Therefore, our study indicates the importance of mastitis management strategies implemented by farmers together with veterinary practitioners, even if mastitis does not appear clinically in organic dairy farms.

• Clinical and Experimental Pediatrics
• /
• v.52 no.10
• /
• pp.1147-1152
• /
• 2009

Purpose:To characterize the pathogens and their antibiotic susceptibilities in more than 24-month-old children with urinary tract infection (UTI) and to study the Escherichia coli antimicrobial susceptibility trend. Methods:We retrospectively reviewed the record of more than 24-month-old children with UTI between January 2003 and December 2008. Positive results for 1 bacterial species with a colony count of ${\geq}10^5CFU/mL$ was considered statistically significant. We analyzed uropathogens and their antibiotic susceptibilities. To investigate E. coli antibiotic susceptibility trend, we compared 2 study periods (group A: 2003-2005 versus group B: 2006-2008) using the chi-square test for trend. Results:In all, 63 bacterial isolates were identified in children with febrile UTI. The most common pathogen was E. coli (77.8%). There was no difference in the resistance patterns of uropathogens during the 2 study periods (P>0.05). Antibiotic susceptibility of the E. coli isolates to aztreonam, cefotetan, cefotaxime, ceftriaxone, cefepime, amikacin, and imipenem was >90% to trimethoprim/sulfamethoxazol, 49% and to ampicillin and ampicillin/sulbactam, 20-25%. Over the 2 study period, the E. coli susceptibilities to most antibiotics did not change: the susceptibility to cefuroxime increased from 74.1% to 95.5% (P=0.046) and that to ciprofloxacin increased from 59.3% to 86.4% (P=0.039). Conclusion:Empirical treatment with trimethoprim/sulfamethoxazole, ampicillin, and ampicillin/sulbactam alone appeared to be insufficient in childhood UTI because of the high resistance of E. coli and other gram-negative uropathogens. Antibiotics for empirical therapy should be selected based on the sensitivity and resistance pattern of uropathogens found in a particular region.

• Clinical and Experimental Pediatrics
• /
• v.45 no.3
• /
• pp.346-353
• /
• 2002

Purpose : Penicillin- and multidrug-resistant S. pneumoniae poses a serious threat to clinicians because the rate of resistance of S. pneumoniae to penicillin in Korea has surged up to the world's highest level. This study was performed to assess the carriage rate, serogroups and antimicrobial susceptibility of S. pneumoniae isolated from oropharynx in children. Methods : From March to July 1998, 209 children under 5 years of age were recruited from five day care centers. The carriage rate for pneumococci was obtained. Antimicrobial susceptibilities were determined with the E-test and agar dilution methods. Serogrouping was performed on 48 of the pneumococcal isolates by the Quellung reaction. Results : The carriage rate of S. pneumoniae was 30.1%. Antimicrobial susceptibility profiles were available for 59 of the isolates. Sixty-six percent of isolates were not susceptible to penicillin, and multidrug-resistance was observed in 76.3% of the isolates. A high proportion of the penicillin-resistant strains showed associated resistance to trimethoprim-sulfamethoxazole, tetracycline, erythromycin, and oxacillin. The most prevalent oropharyngeal serogroups were 19, 6, 3, 23, and 29. Resistance of the pneumococcal isolates to penicillin was different according to the serogroups. All of the strains of serogroup 19, 23, and 29 was resistant to penicillin but 87.5% of serogroup 3 strains were susceptible to penicillin. Conclusion : The resistance rate of S. pneumoniae isolated from oropharynx in children was very high to penicillin and other antimicrobial agents. For the reduction of the drug-resistant rate of S. pneumoniae, clinicians should be required to be more judicious in their use of antimicrobial agents.

• Korean Journal of Veterinary Research
• /
• v.28 no.1
• /
• pp.83-87
• /
• 1988

The in vitro drug susceptibility of 83 strains of Bordetella bronchiseptica recovered from Korean pigs with atrophic rhinitis was investigated by the use of disk diffusion method. The majority of the organisms were highly resistant in order of prevalence to penicillin(98.7%), ampicillin(91.5%), streptomycin(90.3%), triple sulfa(83.1%), and trimethoprim/sulfamethoxazole(70.7%) while none of them were resistant to gentamicin, only 3.6% to colistin, chloramphenicol and kanamycin and 6.0% to tetracycline. The percentage of the organism resistant to bicozamycin, cephalothin and neomycin were 34.9%, 34.1% and 18.4%, respectively. A high prevalence of multiple drug resistance was observed and the 3 most common resistant patterns among 35 patterns noted were Am Pc Sm Sss Sxt(26.5%), Am Cf Pc Sm Sss Sxt(12.%) and Am Bm Pc Sm Sss Sxt(9.6%) patterns.