Bacterial cold water disease, enteric red mouth disease and frunculosis are the common bacterial diseases of fish worldwide. The etiologic agents of these diseases are Flavobacterium (F.) psychrophilum, Yersinia (Y.) ruckeri and Aeromonas (A.) salmonicida subsp. salmonicida, respectively. In this study, a multiplex polymerase chain reaction (m-PCR) method with YER8/10-Fer3/4-FP1/3 primer pairs which can identify these fish pathogens simultaneously was developed and optimized. In optimized conditions, neither false specific nor nonspecific amplification occurred. The detection limits of the m-PCR method using DNA extracts from dilutions of pure cultures of bacteria were 35 pg for Y. ruckeri and F. psychrophilum and 70 pg for A. salmonicida subsp. salmonicida. It was determined that 15 CFU Y. ruckeri and F. psychrophilum and 30 CFU A. salmonicida subsp. salmonicida could be detected by m-PCR developed using genomic DNA extracted from dilutions of the suspensions. The detection limits in the presence of tissue debris were 125 CFU for Y. ruckeri and F. psychrophilum and 250 CFU for A. salmonicida subsp. salmonicida. In conclusion, we submit that the m-PCR method developed and optimized in this study can be used for accurate and rapid identification of these bacteria.
Aeromonas salmonicida/*genetics ; Animals ; DNA Primers/genetics ; Fish Diseases/*diagnosis/*microbiology ; Fishes ; Flavobacterium/*genetics ; Gram-Negative Bacterial Infections/diagnosis/*veterinary ; Polymerase Chain Reaction/methods/*veterinary ; Yersinia rucker/*genetics

An outbreak of footrot has occurred in Debrezeit swine farm that is located 44 km south east of the capital. Among 24 pigs, 75% showed lameness, hot, painful and swollen feet, hemorrhagic bruising of the coronary band, heel erosion, sole ulcers and separation of skin from hoof on hind limbs. Bacteriological examination of the specimen from the affected limbs has shown the involvement of Staphylococcus, Streptococcus and Dichelobacter nodosus. The overt clinical lameness and inability to stand or mount can cause reduced reproductive performance. This preliminary finding thus warrants further epidemiological investigation.
Animals ; Dichelobacter nodosus/isolation&purification ; Disease Outbreaks/*veterinary ; Ethiopia/epidemiology ; Foot Rot/epidemiology/*microbiology ; Gram-Negative Bacterial Infections/epidemiology/microbiology/*veterinary ; Housing, Animal ; Lameness, Animal/epidemiology/*microbiology ; Staphylococcus/isolation&purification ; Streptococcus/isolation&purification ; Swine

Aged ; Animals ; Arcobacter/genetics* ; Chickens ; Diarrhea/microbiology* ; Drug Resistance, Bacterial/genetics* ; Genes, Bacterial ; Gram-Negative Bacterial Infections/veterinary* ; Humans ; Male ; Meat ; Microbial Sensitivity Tests ; Phylogeny ; Poultry Diseases/microbiology* ; Virulence ; Virulence Factors/genetics*

Porcine proliferative enteropathy(PPE) is an enteric disease been caused by Lawsonia intracellularis. It has become one of the critical problems in the pig industry. To investigate the prevalence of PPE in Korea, serum samples of 828 pigs from 65 herds were tested using indirect immunofluorescence antibody technique(IFA). The infection rate in individual pigs varied from 44 to 69%, whereas 100% in pig farms. The infection frequency was 57, 44.9, and 59.4% according to age respectively. Administration of tylosin in feed at a concentration of 110 ppm for 14 days reduced the infection rate of the farms. These data indicated that the high prevalence of PPE may be controlled by tylosin.
Administration, Oral ; Animal Feed ; Animals ; Anti-Bacterial Agents/*therapeutic use ; Antibodies, Bacterial/blood ; Enteritis/epidemiology/prevention&control/*veterinary ; Fluorescent Antibody Technique, Indirect/veterinary ; Gram-Negative Bacterial Infections/prevention&control/*veterinary ; Korea/epidemiology ; *Lawsonia Bacteria/drug effects/growth&development/immunology ; Seroepidemiologic Studies ; Swine ; Swine Diseases/*epidemiology/microbiology/prevention&control ; Tylosin/*therapeutic use

The antibiotic resistance of 16 Aeromonas (A.) salmonicida strains isolated from diseased fish and environmental samples in Korea from 2006 to 2009 were investigated in this study. Tetracycline or quinolone resistance was observed in eight and 16 of the isolates, respectively, based on the measured minimal inhibitory concentrations. Among the tetracycline-resistant strains, seven of the isolates harbored tetA gene and one isolate harbored tetE gene. Additionally, quinolone-resistance determining regions (QRDRs) consisting of the gyrA and parC genes were amplified and sequenced. Among the quinolone-resistant A. salmonicida strains, 15 harbored point mutations in the gyrA codon 83 which were responsible for the corresponding amino acid substitutions of Ser83-->Arg83 or Ser83-->Asn83. We detected no point mutations in other QRDRs, such as gyrA codons 87 and 92, and parC codons 80 and 84. Genetic similarity was assessed via pulsed-field gel electrophoresis, and the results indicated high clonality among the Korean antibiotic-resistant strains of A. salmonicida.
Aeromonas salmonicida/classification/*drug effects/*genetics/i ; Animals ; Anti-Bacterial Agents/*pharmacology ; Bacterial Proteins/genetics ; *Drug Resistance, Bacterial ; Environment ; Fish Diseases/*microbiology ; Fishes ; Gram-Negative Bacterial Infections/microbiology/*veterinary ; Microbial Sensitivity Tests ; Point Mutation ; Polymerase Chain Reaction ; Quinolones/*pharmacology ; Republic of Korea ; Sequence Analysis ; Tetracycline/*pharmacology ; Tetracycline Resistance