The amphotropic murine leukemia virus (MLV) has been shown to infect mammalian species other than mice. If this virus infects and expresses genes in cells of livestock species (cattle, sheep, and pigs) it has potential for use as a vector to produce transgenic livestock. Because the gene-injection technique for producing transgenic animals is inherently inefficient, our laboratory was interested in identifying or constructing retroviral vectors capable of infecting livestock embryos. The infectivity of an amphotropic MLV-based vector for ovine, bovine, and porcine cells was tested. Experiments were also conducted to test the ability of the amphotropic MLV promoter, compared with known strong promoters, to express genes in cells from these species. Results indicated that amphotropic MLV infects and expresses genes efficiently in porcine cells and is, therefore, a potential vector for producing transgenic pigs. Infection was not detected in cells from adult bovine and ovine species; however, low levels of infection, with subsequent gene expression, were detected in cells derived from bovine embryos.

Fecal samples were taken from 402 cows in Posung, Chonnam which was designated as a place for Korean native cattle breeding. Prevalence of internal parasitisms were determined by the fecal examinations using the floatation and sedimentation procedures. 62.9 % of the cows were found as positive cases with excretion of the eggs of Fasciola hepatica in the fecal specimens. Of those infected with F. hepatica 97 cows free of other pathogenic intestinal parasites were chosen for albendazole treatment. Albendazole tablets (10mg/Kg) were administered to the cows twice at the interval of 4 weeks. Blood samples were collected via jugular vein prior to the first treatment, four weeks after the first treatment and four weeks after the second treatment, respectively. At the same time fecal samples were collected for parasitological examinations by sedimentation methods. The mean pretreatment count was 44 fluke eggs per gram of feces, which compared with 27 epg and 17 epg four weeks after the first and second treatment, respectively. Most of the hematological and biochemical values fluctuated within the normal ranges during the experiment. Eosinophil counts were high initially, decreased after the first treatment and thereafter remained steady. The opposite was the case with aspartate and alanine aminotransferases.

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).

The present study was conducted to investigate the Bordetella bronchiseptica infection in Youngnam swine herds during the period of August 1986 to July 1987 and some properties of the organisms isolated from these Korean swine. B. bronchiseptica was recovered from 25 of 70 (35.7%) growing pigs of 4 to 10 weeks of age and from 12 of 13 (92.3%) herds. From 115 slaughter pigs, 58(50.4%) pigs were culture positive and the pigs from 13 of 14 (92.9%) herds were found to be infected with B. bronchiseptica. The majority of biochemical and cultural properties of B. bronchiseptica isolated from Korean swine were identical to those of the standard strain employed and some 97.6% of the isolates showed the characters of phase I organism on primary isolation.