A polyvalent live Eschericia coli oral vaccine were prepared by the use of 5 field isolates of enteropathogenic E. Coli, serotypes 08: K87, K83a, b; 0138: K81, K88a, c; 0141: K85a, b, K88a, b: 0149: K91, K88a, c and 0157: K'V17' K88a, c. Some field experiments were conducted to investigate the effectiveness of the polyvalent live E. coli oral vaccine in the prevention of neandatal colibacillosis in piglets suckling orally vaccinated sows. Seventy-nine pregnant sows in and intensive pig farm were vaccinated with oral vaccine 4 weeks prior to farrowing and 19 sows were chosen for control. The piglets suckling vaccinated sows showed a significant protection against neonatal enteric colibacillosis during the 2 weeks observation period from the farrowing but no significant differences in protection between vaccinated and control group were observed with piglets older than 15 days

3,354 fattening pigs were examined. Gross pathologic alterations of the stomach were classified as normal, with epithelial change, erosion, ulcer and scar formation. In the seasonal prevalence of gastric ulceration, severe ulceration with erosion was shown during autumn and winter, whereas mild ulceration was mainly shown during spring and summer. Of the 3,354 pigs examined, 20.7% were found to be normal. Of the rest, 40% had epithelial changes, followed by erosion (24.7%), ulcer (13.6%) and scar formation (0.9%), respectively. In the prevalence of ulcers in the different regions of the stomach, the fundic region had the highest rate (61.6%) of ulceration, followed by cardiac (21.7%), esophageal (15.0%) and pyloric region (1.7%). The principal gross changes were severe epithelial changes with keratotic proliferation in the esophageal region, and in the fundic region, severe folding of the stomach wall was covered with bloody mucous exudates. Main histopathological changes were inflammatory cell infiltrations in most cases, hemorrhages in acute ulcers and prominent proliferation of granulation tissues in chronic ulcers

The biochemical properties of strains of Staphylococcus aureus isolated from cattle with peracute gangrenous mastitis, acute systemic mastitis and chronic mastitis were examined. Of 261 strains of Staphylococci isolated form quarters with clinical mastitis, 140 (53.6%) were classified as Staphylococcus aureus and 121 (46.4%) were coagulase-negative staphylococci. All the strains of Staphylococcus aureus isolated from quarters with peracute gangrenous mastitis and acute systemic mastitis showed production of alpha heamolysin, coagulase, lipase, phosphatase, nuclease and gelatinase, and fermentation of mannitol. However, of 114 strains of Staphylococcus aureus obtained from quarters with chronic mastitis, 64 (56.1%) possessed alpha lysin, and 43 (37.7%) produced lipase in egg yolk medium. The most common hemolytic pattern of the strains associated with chronic mastitis was Beta type

This study was undertaken to clarify the histopathological changes of pigs naturally infected with hog cholera. Vascular cuffing of the brain was observed in about 97% of the natural cases and all of the experimental cases. Electron microscopic findings on cuffed blood vessels of the brain were endothelial cellular degeneration and infiltration of pleomorphic lymphoid cells. In the rabbits dosed with tissue suspension of the lymphoid organs and isolated hog cholera virus, high body temperature and vascular cuffing of the brain were more significant in pre-injected cases with indian ink

A seroepidemiological survey for antibodies to bovine leukemia virus in dairy and Korean native cattle in Kyungbuk area, Korea [R.] was performed using BLV p and gp antigens by the ID test. In the dairy cattle (Holstein), thirty of 106 sera (28.3%) form 14 dairy farms were positive for BLV antibodies and 12 of 14 pastures were contaminated with BLV. In the Korean native cattle, seventeen (2.4%) of 699 sera from the slaughter house in Taegu city were positive for BLV antibodies. Of 47 gp-ID positive cattle, 5(10.6%) had antibodies to p antigen

The presence of fibrinous thrombi in the blood vessels of multiple organs was observed in chickens which died within approximately 3 days post inoculation. The density of fibrinous thrombi (i.e., the number of thrombi per section) was greatest in the lung, followed by spleen, kidney, liver and heart. The cause of death of the chickens after infection with acute fowl cholera was probably due to an endotoxin (septic) shock accompanied with DIC in multiple organs