A total of 593 mastitic pathogens was isolated from the clinical mastitic milk of dairy cattle in Kyonggi area from March 1984 to February 1988. The mastitic pathogens were further studied bacteriologically and examined for susceptibility patterns to 10 antibiotics. 173 pathogens were isolated in the first year of studies, 205 pathogens in the second year, 122 pathogens in the third year and 93 pathogens in the last year. The pathogens isolated from clinical mastitis were more in summer than other seasons. Staphylococcus spp (50%) and Streptococcus spp (18%) were the main pathogens in the first year of studies but coliforms (15%) and other bacteria (40%) were the main pathogens in the last year of studies. Coliform mastitis occurred only in summer and autumn. Antibiotic susceptibility patterns of the same genuses from clinical mastitis infections in different herds and in different years varied greatly. Therefore, treatment should be selected on the basis of susceptibility test results

A preliminary survey of Sarcocystis species in the slaughtered cattle in Seoul was undertaken during October through December 1987, using digestion diagnostic technique for the heart muscle specimens digested in 0.5 % trypsin solution. Results indicated that 41.5 % of 159 bovine hearts were infected with Sarcocystis proliferative forms. High frequencies in the exotic dairy cattle (42.2%) and the Korean native cattle (41.7%) were noticed in comparison with low frequency in the cross breed (25.0%). No differences were indicated between the sexes of the host animals, although an age difference was noticed as 48.9 % in cattle older than four years in comparison with 39.0 % and 37.1 % in younger than two years and in two to four years, respectively

To determine the prevalence and the morphological identification of two Eimeria species in fecal examinations, a total of 1092 fecal specimens collected during the period of March to December in 1987 was tested by means of flotation technique. The prevalence of two species was revealed as 1.83% and 0.92% in E. bukidnonensis and E. wyomingensis, respectively. The oocysts of E. bukidnonensis measured in range of 41.3 micro m to 49.4 micro m (mean 45.5+-1.7) x 28.8 micro m to 35.3 micro m (mean 32.2 +-1.2), and E. wyomingensis 36.9 micro m to 44.5 micro m (mean 39.8+-1.7) x 26.5 micro m to 29.9 micro m (mean 28.2+-0.9). The oocysts of E. bukidnonensis appeared darker and more robust than those of E. wyomingensis. The striations in the oocyst wall of E. bukidnonensis were more peculiar than in E. wyomingensis. Among the morphological characteristics, the widths could be reliably taken as a differential point of view for two Eimeria species

Some hematological and biochemical indices were assayed in Korean native cattle naturally harbouring Fasciola hepatica infection and compared with uninfected controls. Affected animals revealed reduction in total erythrocyte count and hemoglobin content, and increase in total leukocyte count. Infected cattle had significantly lower levels of serum total protein, serum albumin and magnesium. Significantly higher values were obtained for the serum enzymes asparate aminotransferase and alanine aminotransferase

The bovine serum influencing the growth of swine testicle (ST) cell and the END effect of hog cholera SN test was studied. Bovine whole serum of 16 (76.2%) and 4 (19.0%) samples out of 21 have shown a positive ST cell growth and the END effect, respectively. However, all of 21 (100%) and 8 (38.1%) samples out of 21 serum supernatant fractions, prepared from the bovine whole serum, have shown positive ST cell growth and END effect, respectively