• 대한수의학회지
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• 제23권2호
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• pp.173-178
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• 1983

This paper deals with the isolation of citrate-utilizing variants of Escherichia coli ($Cit^+$ E. coli) from the animals, their biochemical reactivity and antibiotic susceptibility, and whether the citrate utilizing ability is transmissible. One hundred arid twenty-three isolates of $Cit^+$ E. coli were obtained from cattle and pigs. but from other animals, no isolates were obtaied. Antibiotic susceptibility testing of $Cit^+$ E. coli was performed by the agar dilution method, using the following 9 antibiotics, chloramphenicol(CP), tetracycline(TC), streptomycine(SM), kanamycin(KM), colistin(CL), gentamicin(GM), cephaloridine(CR), aminobenzycillin and nalidixic acid(NA). All the variants tested were susceptible to KM, CL, GM, CR and NA. Of all the variants, 80(65%) were resistant to the drugs tested and resistance to TC and SM was most frequent. The transmission of the ability to utilize citrate on Simmons citrate agar at $37^{\circ}C$ was demonstrated in 78(67.8%) out of the 115 $Cit^+$ E. coli. There were no significant difference in the transfer rates of citrate utilizing ability between resistant and susceptible variants to above 9 drugs. Of 123 isolates, 8 were lost their citrate utilizing ability, spontaneously.

• 대한수의학회지
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• 제22권2호
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• pp.161-165
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• 1982

Biochemical and antimicrobial susceptibility tests were conducted on 40 strains of Pseudomonas aeruginosa originated from diseased chicken submitted for diagnosis to this Institute during 1978-80. An extensive study of the biochemical properties revealed that the tested strains can be identified with Pseudomonas aeruginosa. Antibiogram showed that all the strains were susceptible to gentamicin, colistin and amikacin but resist to nitrofurantoin, trimethoprim+sulfamethoxazole, ampicillin, methicillin and kanamycin, and had varing degreed of resistance to other antimicrobials including carbenicillin, sulfomamides, neomycin, streptomycin, tetracycline and chloramphenicol. Three of the most frequent resitance patterns observed were FM SXT AM ME KM CM TC SM NE SSS Pattern, FM SXT AM ME KM CM TC SM NE SSS CB Pattern and FM SXT AM EKM CM TC SM Pattern, and these resistance patterns contained 72.5% of the tested strains.

• 대한수의학회지
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• 제52권3호
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• pp.177-181
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• 2012

Actinobacillus (A.) pleuropneumoniae is the causative agent of pleuropneumonia which is one of the most important respiratory diseases in pigs worldwide. A total of 32 A. pleuropneumoniae isolates from diseased pigs during 2008 to 2010 were serotyped by polymerase chain reaction method. The susceptibility of the isolates to 13 antimicrobial agents were determined by disk diffusion test. In all the 32 isolates examined in this study, serotype 5 (16 isolates: 50%), 1 (7 isolates: 21.9%), 2 (5 isolates: 15.6%) and 12 (1 isolate: 3.1%) were found. Of all tested antimicrobial agents, resistance to oxytetracycline was found in 96.9% of isolates, followed by resistance to amikacin (81.2%), neomycin (68.7%), kanamycin (53.1%), penicillin (50.0%), gentamicin (43.7%), florfenicol (25.0%), ampicillin (18.7%), colistin (9.4%), trimethoprim/sulfamethoxazole, ceftiofur (8.3%), amoxicillin/clavulanic acid (3.1%) and enrofloxacin (0%). Oxytetracycline or florfenicol-resistant isolates were examined for the presence of resistance gene. Among the 31 oxytetracycline-resistant isolates, tetB, tetH and tetO genes were detected in 22 (71%), 8 (26%) and 1 (3%) isolates, respectively. The floR genes were detected in 8 (100%) of the 8 florfenicol-resistant A. pleuropneumoniae isolates.

• 대한수의학회지
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• 제60권3호
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• pp.163-171
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• 2020

This study examined the prevalence of adherence factors, toxin genes, antimicrobial resistance phenotypes, and resistance genes in Escherichia coli (E. coli) isolated from piglets with diarrhea before and after the ban on antibiotic growth promoters (AGPs) in Korea from 2007 to 2018. In this period, pathogenic 474 E. coli isolates were obtained from diarrheic piglets. The virulence factors and antimicrobial resistance genes were assayed using a polymerase chain reaction, and the susceptibility to antibiotics was tested according to the Clinical and Laboratory Standards Institute guidelines. After the ban on AGPs, the frequency of F4 (12.5% to 32.7%) increased significantly, and LT (31.9% to 20.3%) and EAST-I (46.5% to 35.2%) decreased significantly. In addition, the resistance to streptomycin (45.8% to 67.9%), cephalothin (34.0% to 59.4%), and cefazlin (10.4% to 28.8%) increased significantly. Colistin resistance plasmid-mediated genes, mcr-1 and mcr-3, were detected after the ban on AGPs. The results of this study can provide useful data for analyzing the impact of the ban on AGPs on the virulence profiles and antimicrobial resistance of E. coli isolated from piglets with diarrhea in Korea.

• 생명과학회지
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• 제11권3호
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• pp.266-272
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• 2001

A total of 79 Salmonella spp. were isolated from Pusan area in 2000. The serotypes of 79 Salmonella isolates were classified as 42 strains of S. typhi(53.1%), 24 strains of S. enteritidis(30.4%), 9 strains of S. montevideo(11.4%), 2 strains of S. typhimurium(2.5%), 1 strain of S. infantis(1.3%) and 1 strain of S. indiana(1.3%) strains(16.5%) of Salmonella sp. were isolated at May July, respectively. The isolates of S. typhi were sensitive to most sntibiotics except streptomycin. All isolates of S. typhi were especially sensitive to tobramycin, gentamicin, colistin, kanamycin, samikacin, sulfamethozazole/ trimethoprim, cefriaxone, ceftazdime, cifrofloxacin, cefoxitin and cefotaxime. Isolates of S. enteritidis wer presented higher resistance than isolates of S. typhi. Twenty-four strains of S. enteritidis were sensitive to kanamycin, amikacin cifrofloxacin, cefoxitin and cefotaxime, however 13 strains(54.2%) of S. enteritidis were resistant to carbenicillin, ampicillin and ticarcillin. Nine strains of S. montevideo were sensitive to most antibiotics except carbenicillin and streptomycin. Each 1 stain of S. indiana and S. infantis was sensitive to most antibiotics used in this study except streptomycin. Three kinds of resistant pattern (CB, SM, TE, AM, TC). In the case of S. enteritidis isolates, 9 kinds resistant pattern were detected. Most frequent resistant pattern of S. enteritidis isolates was CB, AM, TC type(16.7%)

• 한국동물위생학회지
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• 제19권2호
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• pp.115-125
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• 1996

A total of 315 microorgainisms were isolated from 256 pneumonic lung samples of pig in abattoirs of northern Chungnam area during February to November 1994, and Identified 97 strains as Pusteurella multocida, 89 strains as Staphylococcus spp, 54 strains as Streptococcus spp, 22 strains as Mycoplasma spp, 21 strains as Escherichia coli, 18 strains as Haemophilus parsuis, 11 strains as Corymebacteroi, pyogenes, and 3 strains as Acrinobacillus spp by Gram's and Dienes stain, and biological properties test Involved API system. After that, they were examined anti biotic susceptibility for ampicillin(AM), cephalothin(CF), chloramphenicol(CP), erythromycin(EM), kanamycin(KM), gentamicin(GM), neomycin(NM), penicillin(PC), streptomycin(SM), tetracycline(TE), tiamulin(TIA), tylosin(TYL), methicillin(DP), colistin(CL) and trimet hoprim(SXT). In antibiotics susceptibility test, 293 isolates except Mycoplasma spp 22 strain were highly susceptible to DF(79.2%) and AM(76.2%), but resistant to PC(14.0%), NM(19.5%) and KM (23.2%) The multiple drug resistant patterns were noted in most isolates, whereas only 7 isolates resistant to single drugs.

• 대한수의학회지
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• 제39권6호
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• pp.1091-1098
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• 1999

Antimicrobial susceptibility, plasmid profiles and distribution of toxA gene were investigated in Pasteurella multocida isolated from pneumonic lung lesions of swine. The bacteria were highly susceptible to norfloxacin, cabenicillin, enrofloxacin and chloramphenicol, but resistant to colistin, sulfamethoxawle/trimethoprime, bacitracin, streptomycin. Sixty percentage of the isolates was resistant more than 2 drugs used in this experiment and 21 strains (23.6%) were resistant more than 5 drugs. This phenomenon meant that they had highly multi-drugs resistance. In the analysis of plasmid profiles, nineteen strains (47.5%) of 40 P multocida isolates harbored plasmids, ranging from 53.3kb to 2.49kb in size and the plasmid profiles could be classified into 5 groups. However, there was no relationship between the size and the profile of plasmid and the resistance pattern of antimicrobial agents. Thirty strains of 39 P multocida isolates (77%) investigated by PCR harbored toxA gene. This result suggested involvement of the ToxA protein expressed from the gene in pneumonic pasteurellosis of swine.

• 대한수의학회지
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• 제32권1호
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• pp.63-76
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• 1992

A study on the isolation of Yersinia from the feces of healthy pigs and the biotype and serotype and susceptibility to 16 antimicrobials was carried. Out of 853 pigs, Yersiniae were isolated from 349 pigs(40.9%). Of 349 isolates, 289 isolates(82.8%) were Yersinia enterocolitica and 54(15.5%) were Y kristensenii, 3(0.9%) were Y pesudotuberculosis and the rest 3(0.9%) were Y prederiksenii. Out of 289 isolates of Y enterocolitica, the predominants biotype was 3B comprising of 165 isolates(57.1%) and followed by biotype 2, comprising of 49 isolates(17.0%), bioptype 3A, comprising of 41 isolates(14.2%) and biotype 4 comprising of 23 isolates(8.0%). And the predominant serotype was 0 : 3 comprising of 231 isolates(79.9%) and followed by serotype 0 : 9 comprising of 42 isolates(14.5%) and 0 : 21 comprising of 10 isolates(3.5%). Y. enterocolitica were resistant to cephalothin(99%), novobiocin(99%), erythromycine(83%), ampicillin(83%) and carbenicillin(81%) and susceptible to amikacin(100%), colistin(100%), gentamicin(100%), kanamycin(100%), polymyxin B(100%), tobramycin(100%), chloramphenicol(99%), nalidixic acid(99%), neomycin(99%), streptomycin(99%) and tetracycline(99%). Most strains of biotype 2/serotype 0 : 9 were susceptible to carbenicillin(100%) and ampicillin(61%) but the other biotype/serotypes were resistant to these antibiotic.

• 한국축산식품학회지
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• 제26권3호
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• pp.394-401
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• 2006

Forty Clostridium perfringens isolates were obtained from twelve animal products, following the examination of eighty six beef, pork, broiler chicken and salami meat products, and eleven milk powder products. There were 21 isolates from salami stored at $25^{\circ}C$, 3 isolates from pork, 4 isolates from beef, 9 isolates from broiler chicken, and 3 isolates from milk powder. Only the cpa gene encoding a toxin among the 5 toxin genes tested (cpa, cpb, etx, iap, and cpe) was detected in all forty isolates, suggesting contamination with C. perfringens type A. DNA fingerprinting analysis using PCR of the tRNA intergenic spacer (tDNA-PCR) and the 16S-23S internal transcribed spacer (ITS-PCR), and randomly amplified polymorphic DNA (RAPD) analysis were attempted to differentiate the isolates. RAPD analysis was the most discriminating method among the three PCR analyses. Isolates from the same products tended to show similar RAPD patterns. Antimicrobial susceptibility tests showed that some isolates from broiler chickens had the same antibiogram with multiple resistance to streptomycin, colistin, and ciprofloxacin. Antibiograms were similar between isolates from the same livestock products, but differed considerably between the products.

• 한국동물위생학회지
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• 제25권1호
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• pp.75-86
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• 2002

Outbreaks from September 1999 to July 2000 of blackleg in 4 milking and fatting cattle farms in the vicinity of Munkyong(northwestern part of Gyeongbuk province) were investigated biochemical characteristics of isolates and were surveyed epidemiological works during the period of 2 months from August to September 2000. Clostridium chauvoei, the etiological agent of blackleg is a serious pathogen of cattle and sheep causing fever, depression and lameness with high mortality in growing phase of 6 to 18 months old mainly beef cattle. Biochemical and cultural properties of 4 isolated Cl chauvoei were identical to those of reported results and isolates were susceptible to ampicillin, bacitracin, chlorarnphenicol, cephalothin, ciprofloxacin, erythromycin, norfloxacin, penicillin, and tetracycline, while they were resistant to amikacin, colistin, gentamicin, kanamycin, neomycin, streptomycin and trimethoprim-sulfamethoxazole. In the results of epidemiological survey, outbreak farms that concentrated region of milking or fatting cattle in each sites were so close contact within a radius of about 1km that they are separated only by wire fence or shrub harrier and flies, rodents, wild cats and birds could have the chance to move around between those farms. The origin of the outbreak blackleg were uncertain, but the transmission between farms were mainly through the movement of farm personnel, vehicles which were struck the feces or manures from farm and other mechanical factors such as flies, rodents and birds furthermore occurred 4 farms were not vaccinated. In conclusion, a periodic disinfection, vaccination and quarantine prevention are ideal methods of damage reduction by blackleg.