Search

A plaque assay for duck plague virus was developed for a chicken embryo-adapted virus and a duck lethal virus and used to determine the identity of these viruses. Using the plaque inhibition neutralization test, duck plague virus was differentiated from Newcastle disease, fowl plague, and duck hepatitis viruses. The plaque morphology is described.

Thirty-three pigs in three groups of nineteen, ten, and four pigs were infected with three different African swine fever (ASF) virus isolates, respectively. All virus isolates were attenuated to varying degrees by passaging in cell cultures, and they retained sufficiently low virulence to produce subacute and chronic infections in pigs. Sera collected at various intervals were tested for antibody activity by the immunoelectroosmophoresis, agar gel diffusion precipitin, and complement-fixation tests using a modified Kolmer technique. Results clearly indicated that the immunoelectroosmophoresis test is a rapid (30 minute) and accurate method with extreme sensitivity and superior to the complement-fixation and agar gel diffusion precipitin tests in detecting antibody against ASF virus. Possible use of this method in detecting ASF virus infection is suggested.