• Journal of the Korean Society of Tobacco Science
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• v.7 no.2
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• pp.123-128
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• 1985

The incitant of soft rot on burley tobacco leaves in the curing vinylhouse was identified as Erwinia carotovra subsp. carotovora on the basis of its physiological characters. The bacterium yew best at $25^{\circ}C$ and $30^{\circ}C$, but no growth was detectable at $40^{\circ}C$ in the nutrient broth for 24 hours period. Burley tobacco leaves inoculated with the bacteria (Ecc) produced typical soft rot lesions when the incubation temperature was 25 to $30^{\circ}C$ and the relative humidity was more than 8075, however, the lesion development was suppressed when the temperature was $40^{\circ}C$ and the relative humidity was below 80%. Significant negative correlation was found between hanging space in the curing vinylhouse and the incidence of soft rot on the tobacco leaves harvested in a rainy day regardless of streptomycin treatment.

• Journal of Veterinary Clinics
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• v.19 no.2
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• pp.159-164
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• 2002

The present study was conducted to investigate the antibiotic resistance of 24 Salmonella gallinarum isolated from 48 chicken samples of diagnosed fowl typhoid cases during the period from November 1998 to November 1999. And the isolates of S gallinarum were also tested for their invasion abilities to experimental infection as one of virulence tests, and the presence of virulence-related plasmid in S gallinarum isolates. The results obtained through this study were summarized as follows; 1. All of isolates from 48 cases of 24 farms were identified S gallinarum by biochemical and serological tests.2. Antimicrobial drug resistance test against 24 isolates showed that the isolates were resistant to Colistin(95.8%), and Penicillin(79.2%), Polymyxin B(75.0%), Streptomycin (65.2%), Gentamycin(54.2%), and Tetracycline(33.3%). 3. Mortality in chicken following peroral inoculation of four isolates of S gallinarum during 14-days inoculation pecked at 5 days(40%) after inoculation and all of experimental chickens died within 13 days after inoculation.4. Based on the pattern and number of isolated plasmid from each isolate, plasmid profiles were divided into five groups; group I with 3 plasmids, group II to group IV with 4 plasmids and group V with 5 plasmids.

• Korean Journal of Veterinary Service
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• v.17 no.2
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• pp.89-94
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• 1994

The present study was conducted to investigate the incidence of pasteurella multocida(p. multocida) infection and some properties of the isolated organisms from the swine herds in Eastern Kangwon during the periods from March 1993 to November 1993. The results obtained were summerized as follows： 1. The lungs of 180 slaughtered pigs were sampled and p. multocida was isolated from 38 pigs (21.1%) and cultured positive. 2. The majority of biochemical md cultural properties of the p. multocida isolates were identical to those of the standard strains. 3. We investigated the capsular serogroup and drug susceptibility of 38 Isolates of p. multocida from pigs with pneumonic lesions 4. p. multocida isolateds were typed for capsular serogroupes A by hyaluronidase inhibition of capsule and D by acriflavin auto agglutination. Most isolates(55.3%) were type A, 15.8% were type D, and the remaining 28.9％ were untypable 5. In antimicrobial susceptibility test these isolates of p. multocida were susceptible in order of colistin(94.7%), ampicillin(94.7%), cepalothin(92.1%). gentamicin(92.1%), amikacin(89.5%), but the majority of them were resistant in order of neomycin(26.3%), teracycline(23.7%), streptomycin( 15.8%)

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.99-105
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• 1974

A total of 2,053 quarter milk samples of 518 dairy cows from 46 herds were examined for mastitis and results obtained were as follows: 1. A total of 428 quarters(20.8%) of 271 dairy cows(52.3%) from 41 herds(89%) were found to be infected with mastitis. 2. It was found that 71 quarters(3.5%) of 41 cows(7.9%) from 21 herds(45.6%) were clinical mastitis and 357 quarters(17.3%) of 230 cows(44.4%) from 20 herds (43.4%) were subclinical mastitis. 3. The main causative organisms of the mastitis were Staphylococcus aureus(26%), Streptococcus uberis(16%), and Streptococcus agalactiae(10%). 4. The majority of causative organisms were very resistant to colistin(85.9%), penicillin(67%), and streptomycin(39%). Most of the other drugs were highly effective as inhibitor for the most causative organisms in vitro. However sulfisoxazole was moderatively effective against them.

• Korean Journal of Veterinary Research
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• v.14 no.1
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• pp.91-97
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• 1974

A total of 820 dairy cattle were examined formastitis by California mastitis test method and 181 dairy cattle were examined bacteriologically according to the method of Connecticut mastitis control program. The results obtained were as followings: 1. Milk samples from 1.231(38.1%) of 3,225 quarters and 568(69.3%) of 820 dairy cattle were positive for mastitis by California mastitis test method. 2. Among 181 cattle examined bacteriologically by the method of Connecticut mastitis control program 159(22.9%) quarters of 102(56.4%) cattle were infected. Clinical mastitis was found in 5 cattle. 3. Important causative organisms were found to de Staphylococcus aureus(44.8%), Streptococcus agalactiae(21.5%), and non-str, agalactiae Streptococcus(26.4%). Corynebacterium ssp., Pseudomonas spp., Coliforms and Yeasts were also occasionally found to be causative organisms. 4. Strains of Staphylococcus aureus isolated from bovine udders were tested for sensitivity to antibiotics. The rates of resistant strain were 13.7%, 11.8%, 8.8%, 5.9%, 100%, 4.9% and 4.9% for penicillin G, streptomycin, terramycin, erythromycin, chloramphenicol, ampicillin and kanamycin, respectively.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.427-434
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• 1990

The purpose of this study was to examine O serotypes, colicin and hemolysin production. antibiotic susceptibility and haemagglutinating ability to animal erythrocytes among Escherichia coli strains isolated from pigeons in Taegu province. Of the 166 strains isolated, 28 strains (16.9%) were classified into 6 O serotypes and their types were O20(42.9%), O15(17.9%), O139(14.3%), O101(10.7%), O149(7.1%) and O8(7.1%). Of the 166 strains isolated, none was hemolytic and 3(1.8%) were colicinogenic. Antibiotic susceptibility test of Escherichia coli isolates was performed by the agar dilution method, using ampicillin, chloramphnicol, gentamicin, rifampicin, streptomycin (Sm), nalidixic acid, sulfadimethoxine and tetracycline (Tc). Forty four strains (26.5%) were resistant to one or more drugs and the most common resistance patterns were SmTc (27.3%). Of the 44 drug resistant strains, 6 strains haemagglutinated erythrocytes of chicken, guinea pig and 2 of the 6 strains agglutinated goose erythrocytes.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.67-75
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• 2007

Environmental mastitis has increased particularly in well-managed or low somatic cell countherds that have successfully controled contagious pathogens. Major pathogens of environmental mastitisare Escherichia coli (E. coli) and Streptococcus uberis. The present study was conducted to investigate1,865 quaters of 241 Korean dairy farms from 2001 to 2004. Prevalence of major gram-negative bacteriaisolated from mastitis milk were E. coli (22.7%) and Enterobacter spp. (16.3%) in coliforms and Pseudomoassp. (10.3%) and Serratia spp. (7.9%) in non-coliforms. The results on antibiotic susceptibility by agardifusion test against these pathogens were 86.7% in piperaciliin, 94.6% in cefepime, 85.5% in amikacin,87.7% in gentamicin and so on. In contrast, the susceptibility against ampicillin (41.9%), cephalothin (9.9%),streptomycin (39.9%) and tetracycline (46.7%) appeared to be below 50%. Gram-negative bacteria showed(96.8%). Acording to year, distribution of high $256{\sim}64{\mu}g/ml$ on cephalothin get increased, but the othersare diferent. These findings demonstrate that major gram-negative bacteria were E. coli and Enterobacterspp. isolates, and often encountered the diverse antibiotic resistant patterns.

• YAKHAK HOEJI
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• v.43 no.1
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• pp.68-76
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• 1999

Phenoxazinone synthase catalyzes the oxidative condensation of two molecules of substituted o-aminophenol to the phenoxazinone chromophore of actinomycin. Mutant strain, Streptomyces sp. V-8-M-1 producing higher phenoxazinone synthase, was obtained from Streptomyces sp. V-8 by treatment of N-methyl-N'-nitro-N-nitrosoguanidine. The phenoxazinone synthase was purified from extract of mutant strain of Streptomyces sp. V-8-M-l by successive steps of streptomycin sulfate, ammonium sulfate precipitation. DEAE-cellulose and Sephadex G-200 column chromatography. Molecular weight of the enzyme was 360,000 daltons. The enzyme was composed of octamer of a single subunit of 45,000 daltons. The Km value and Vmax value for 3-HAA were $14.9{\;}{\mu}M$ and 9.5 mg/U, respectively. The optimal pH and temperature for the enzyme activity were 9.0 and $25~30^{\circ}C$, respectively. Treatment of the enzyme with group specific reagents, phenylglyoxal, p-hydroxymercury-benzoate, Nbromosuccinimide, 5.5'-dithiobis-nitrobenzoic acid and ethylmaleimide resulted in loss of enzyme activity, which shows arginine and cysteine residues are at or near the active site.

• Korean Journal of Veterinary Service
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• v.22 no.1
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• pp.85-92
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• 1999

This study was investigated resistance on disinfectants and antibiotics of Clostridium chauvoei isolated from dairy farm in Kyongbuk province. The results obtained were summarized as follows ; C chauvoei isolated from dairy farm were susceptible to norfloxacin, penicillin, tetracycline, erythromycin, enrofloxacin, bacitracin, tyrosine, cephalothin and cefazolin but resistant to gentamicin, kanamycin, sulfamethoxazole＋trimethoprim, amikacin, neomycin streptomycin, colistin. In effect on disinfectants, C chauvoei was inhibited completely to growth in mercuric bichloride ($HgCl_2$), harasol(sodium hypochloride 4-6%), long-life(high boiling tar acids et al), and phenol($C_6$$H_5$OH), but growth in all-stop(didecyl dimethyl ammonium chloride 10%), powercide(potassium monopersulphate 50% et al), antec vercon-s(triple salt 50% et al), and taego-51(6-alkyl-2.6-diaza-hexane-carbonic acid-1ㆍHCl et al). The effect of disinfectant was excellent in mercuric bichloride and harasol.

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.139-146
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• 2009

Bovine brucellosis is a zoonosis, long incubation period and chronic infectious disease, usually caused by Brucella abortus. This study was carried out to investigate the biotyping and biochemical characterization of B. abortus isolated from 208 farm 871 korean cattle and holstein diagnosed brucellosis by serological positive in Gyeongbuk province during the period from 2002 to 2006. B. abortus was isolated from 124 (14.2%) of 871 cattle, and isolated 110 (13.4%) of 820 Korean cattle and 14 (27.5%) of 51 holstein in breed. The uterus of korean cattle was isolated in 8 (17.8%) of 45 cattle and supramammary lymph none of holstein was isolated 11 (68.8%) of 16 cattle. 101 (12.5%) of 810 serological positive blood samples were isolated B. abortus. The isolation rate of B. abortus was correlated with antibody titers. The biochemical characterization of isolates was non-hemolytic, production of H$_2$S, oxidase-positive, catalase-positive, hydrolyzation of urea and growth of basic fuchsin dye medium. As a result, all of isolates was identified B. abortus bv 1. 124 isolates were susceptible to ampicillin, lincospectin, amikacin, gentamicin, kanamycin, neomycin, streptomycin, tetracycline, ciprofloxacin, norfloxacin and enrofloxacin.