The first outbreak of aujeszky's disease (AD) was identified from piggery located at the southern part of Korea in July, 1987. This piggery suffered from a significant economic loss caused by unexpected piglet mortality and reproductive failure. Etiologic viral agents were isolated from tonsil and spleen of the infected piglets, and the isolates produced a typical cytopathic effect of herpesvirus with giant cell formation when inoculated in many different cells. Subsequently the field isolates were characterized as suid herpesvirus I by cross-neutralization test and indirect fluorescence assay utilizing specific monoclonal antibody, and proved to be a pathogenic strain of AD virus(ADV).

Concentrations of serum IgA, IgG, and IgM were determined for 829 adult Beagles from a commercial kennel in which several IgA-deficient dogs had been identified previously (index kennel). These values were compared with measurements of 100 adult dogs from another Beagle kennel (control kennel). After adjustment for differences in the ages and gender of the dogs, dogs from the index kennel had significantly (P less than 0.0001) lower IgA concentrations (mean, 46 mg/dl). Regardless of kennel, males had significantly (P less than 0.01) higher IgA concentrations than did females. Dogs in the control kennel had significantly (P less than 0.04) higher IgG concentrations (mean, 2,649 mg/dl) than did dogs in the index kennel (mean 2,478 mg/dl), and female dogs in the control kennel had significantly (P less than 0.05) higher IgM concentrations (mean, 189 mg/dl) than dogs of either sex in the index kennel (mean, 162 mg/dl) or male dogs in the control kennel (mean, 163 mg/dl). For both sexes, concentrations of IgA, IgG, and IgM increased with age.

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

Twenty-eight porcine rotavirus were isolated from piglets with diarrhoea in Chonnam Province. According to the age, 41 to 60 day old pigs showed the highest isolation frequency among the post weaning pigs. The characteristics of the field isolates were determined by electronmicroscopy(EM), immunofluorescent assay(FA), and electrophoretic migration patterns of the genome profiles. Some of the isolates showed remarkable haemagglutination activity against rabbit and dog erythrocytes, ranging from 4 to 2848, respectively. At least 3 serotypes of porcine rotavirus were recognized by serum neutralization test using serotype specific rotavirus hyperimmune sera

This study was conducted to isolate etiological agents from the 103 scouring piglets in Kyongnam area and also carried out antimicrobial drug susceptibility test and epidemiogical survey. The incidence of scouring piglet was most prevalent in 81.6% at the age of 2 to 4 weeks after birth, while the rate was less than 10% at the age of 5 to 6 weeks and under 1 week after birth. When comparing the isolation frequency of each etiological agent, enteropathogenic E. coli was most prevalent in 46.6%, thermophilic Campylobacter in 26.2% and Salmonellae was in 8.7% in that order. In the OK serotyping for 117 isolates of enteropathogenic E. coli, type 0141 : K85(20.5%), 0157:K88ac(14.5%), 0138:K81 and 0149:K91 (13.3%) were encountered most frequently. In the biotyping for 27 isolates of thermophilic Campylobacter, most strains of C. jejuni belonged to type I (50.0%) and II (25.0%), and most strains of C. coli belonged to biotype I (78.9%). In the serotyping for 9 strains of Salmonellae, 3 strains were grouped as D, 2 strains as C and 1 strain each was group B and E. The other 2 strains were untypable. The 117 isolates of enteropathogenic E. coli were resistant more than 90% to erythromycin, penicillin, tetracycline and streptomycin, whereas about 90% of the isolates were sensitive to kanamycin and gentamicin. In the case of Salmonellae, all of the isolates were resistant to penicillin, but about 89% of the isolates were sensitive to gentamicin and colistin. All of C. jejuni and C. coli isolates were resistant to cephalothin, but more than 89% of C. jejuni and C. coli were sensitive to kanamycin and gentamicin