[Isolation of lymphocyte cultures from leukemic cattle and electron microscopic study of the leukemia virus]. / Poluchavane na limfotsitni kulturi ot bolni ot levkoza goveda na elektronnomikroskopsko prouchvane na virusa na levkozata.

Several methods were employed to obtain lymphocyte cultures from blood samples taken from normal cattle and from cattle affected with enzootic leukosis. Biologic and virologic experiments revealed that the cultures from diseased cattle contained an oncogenic leukosis virus, while those obtained from healthy animals were exempt from such virus. Electron microscopy was applied to study the morphologic aspects of the bovine leukosis virus with a total of 18 lymphocyte cultures. The viral particles noted were shown to have typical configuration and size of type C oncogenic viruses as described in the literature--possessing a central dense nucleotide and double membranes. Seen were also various stages in the development of the virus. Mature virus particles were likewise observed in a stable cell line FLK (percent of the virus) as well as in ultrathin cross sections of the spleen of leukosis-affected animals.

[Development of ELISA for demonstrating antibodies to the swine pestivirus]. / Razrabotvane na ELISA za dokazvane na antitela sreshtu pestivirusa po svinete.

An indirect variant of the enzyme linked immunosorbent assay with the classic form of swine fever has been worked out. The test makes it possible to assess the level of antibodies with a great number of animals over a short period of time with no special equipment. The method has proved promising in taking prophylactic measures.