Thirty-one Campylobacter jejuni isolates (22 from various local sources, 9 from imported chicken meats) were subtyped with PFGE and flaA typing to investigate their genetic relatedness. Based on a 90% similarity criterion, 23 and 21 genotypic patterns were formed by PFGE and flaA typing, respectively. The discriminatory indices for PFGE, flaA typing, and a composite analysis of PFGE and flaA typing were 0.9785, 0.9527, and 0.9871, respectively. Similar patterns in composite analysis were observed between sources (cattle and chicken, and cattle and human), indicating that reservoir animals may have been the source of human campylobacteriosis. Therefore, strict hygiene measures from farm to table should be implemented to prevent diseases due to C. jejuni in humans.

Salmonellosis is one of the most common food-borne diseases in both humans and animals. The recovery of Salmonella from fecal and environmental samples by bacteriological assays takes several days. Polymerase chain reaction (PCR) has become an important technique for the rapid detection of Salmonella in a variety of samples, including feces. For rapid identification of Salmonella by PCR, 1 mL of enrichment culture was harvested after overnight incubation and DNA was extracted by heat lysis. To investigate the optimal conditions for rapid PCR detection of Salmonella, three different primer sets and three different enrichment media were used on a panel of Salmonella strains and a panel of non-Salmonella strains. The results showed that selenite cysteine enrichment broth and a primer set designed for the invA gene provided the most specific and rapid detection of Salmonella by PCR after the enrichment step.

The objective of this study was to evaluate several types of uterine bacteria in Hanwoo. uterine bacteria from randomly selected 5 uterus was collected by flushing methods into a sterilized 1.5 ml centrifuge tube and was inoculated onto MacConkey agar and blood agar, respectively. After being incubated for 5% CO2, aerobic or anaerobic condition at 37℃ during 48h, bacterial colonies were selected and re-inoculated onto blood agar plates. Re-cultured colonies were identified by Gram staining and finally identified using Vitek system. The identified bacteria were Staphylococcus lentus, Staphylococcus sciuri, Staphylococcus vitulinus, Staphylococcus warneri of Gram (+) and Rhizobium radiobacter, Sphingomonas paucimobilis of Gram () bacteria. Although, pathogenicity of identified bacteria was unclear, the bacteria can have an effect on the uterine microenvironment. Therefore, repetitive research will be required to determine the effects of bacteria in cattle exposed to a various environment.

Egg yolk immunoglobulin (IgY) is the antibody in egg yolk and can be produced in egg yolk by immunizing hens with antigens. IgY is functionally equivalent to mammalian IgG. It is found in the serum of the chicken and is passed from the mother chicken to the embryo via the egg yolk, a process that results in a high concentration of IgY in the egg yolk. The objective of this study was to evaluate the efficacy of specific IgY against enterotoxigenic Escherichia coli (ETEC) K99, Salmonella Typhimurium and Salmonella Choleraesuis that cause porcine bacterial diseases. To prepare specific IgY, Hy-Line Brown chickens were vaccinated with killed vaccine complex including E. coli K99, S. Typhimurium and S. Choleraesuis. The chicken egg yolk antibodies were purified from egg yolk by ammonium sulfate precipitation and the quality of the final preparation was confirmed by sodium dodecyl sulfate polyacrylamide gel electro-phoresis (SDS-PAGE). Titres of specific IgY in final preparations were measured by an enzyme-linked immunosorbent assay (ELISA). Antibody titers peaked at 3 weeks regardless the bacterial types and the similar patterns of immune response were observed for respective pathogens. In growth inhibitor test, specific IgY showed inhibitory effect on bacterial growth. After 0, 3, 6 and 12 hour of incubation with specific IgY (100 ㎍/㎖, 250 ㎍/㎖, 500 ㎍/㎖), there was a significant decrease in the growth (A 600nm ) of E. coli K99, S. Typhimurium and S. Choleraesuis compared to nonspecific IgY and controls. In BALB/c mice, the effect of specific IgY (100 ㎎/㎏, 250 ㎎/㎏) on bacterial challenges was investigated by intramuscular injection and oral administration of bacteria. Mice treated with specific IgY showed high survival rate though there was no significant differences on blood biochemichal examinations between treated and untreated groups. These results indicate the potential of specific IgY for the treatment of porcine bacterial diseases caused by E. coli K99, S. Typhimurium and S. Choleraesuis.

The antimicrobial susceptibility of the 41 Bordetella bronchiseptica isolates was tested by using the Kirby-Bauer agar disk diffusion method. The B. bronchiseptica isolates were found to be sensitive to amoxicillin/clavulanic acid (100%), gentamicin (100%), neomycin (100%) and amikacin (97.6%), whereas they were resistant to streptomycin (100%), trimethoprim/sulfamethoxazole (100%), penicillin (100%) and ampicillin (97.6%). All the B. bronchiseptica isolates resisted to at least 4 antimicrobial agents and totally 8 different combinations of multiple antibiotic resistance patterns were noted. All of the B. bronchiseptica isolates, except one, were simultaneously resistant to streptomycin, trimethoprim/sulfamethoxazole, penicillin and ampicillin. The observed antibiotic resistance is not plasmid mediated as plasmids were absent from all the B. bronchiseptica isolates.