Efficacy of GPE strain live attenuated vaccine and CP7_E2alf strain recombinant live vaccine (marker vaccine) against Japanese epidemic classical swine fever virus isolated in 2019 and DIVA discrimination ability of the marker vaccine.

Classical swine fever (CSF) re-emerged in Japan in 2018, with the epidemic virus identified as genotype 2.1, which is moderately virulent and more difficult to detect and control than the highly virulent strain. Domestic pigs were administered with GPE strain live attenuated vaccine (GPE vaccine) for outbreak management.

Analysis of a pair of END+ and END- viruses derived from the same bovine viral diarrhea virus stock reveals the amino acid determinants in Npro responsible for inhibition of type I interferon production.

The Exaltation of Newcastle disease virus (END) phenomenon is induced by the inhibition of type I interferon in pestivirus-infected cells in vitro, via proteasomal degradation of cellular interferon regulatory factor (IRF)-3 with the property of the viral autoprotease protein N(pro). Reportedly, the amino acid residues in the zinc-binding TRASH motif of N(pro) determine the difference in characteristics between END-phenomenon-positive (END(+)) and END-phenomenon-negative (END(-)) classical swine fever viruses (CSFVs). However, the basic mechanism underlying this function in bovine viral diarrhea virus (BVDV) has not been elucidated from the genomic differences between END(+) and END(-) viruses using reverse genetics till date.

Molecular, biological, and antigenic characterization of a Border disease virus isolated from a pig during classical swine fever surveillance in Japan.

In the current study, molecular, biological, and antigenic analyses were performed to characterize Border disease virus (BDV) strain FNK2012-1 isolated from a pig in 2012 in Japan. The complete genome comprises 12,327 nucleotides (nt), including a large open reading frame of 11,685 nt. Phylogenetic analysis revealed that FNK2012-1 was clustered into BDV genotype 1 with ovine strains.

Methods to select suitable fetal bovine serum for use in quality control assays for the detection of adventitious viruses from biological products.

Production of biological products, especially vaccines, usually requires materials derived from animals, and there are always risks that animal pathogens derived from these materials could contaminate the final products. Detection of adventitious agents is performed by quality control tests. In these biological assays, animal derived materials are also used and another problem arises, as fetal bovine serum (FBS) is used as an ingredient in tissue culture media.

A taxonomic study on erysipelothrix by DNA-DNA hybridization experiments with numerous strains isolated from extensive origins.

The purpose of this study was to clarify the taxonomic relationship between all the serovars and species of the genus Erysipelothrix by performing DNA-DNA hybridization experiments, the customary criterion for separation of bacterial genospecies. A total of 93 strains were isolated from a wide variety of sources, including pigs affected with acute or chronic erysipelas, other diseased animals, healthy animals, fish, retail meats, and environmental materials from throughout the world during the period 1958 to 1996. The present data on phenotypic characterization and DNA relatedness values demonstrate that 24 strains (96%) of E.

Genomic analyses of bovine viral diarrhea viruses isolated from cattle imported into Japan between 1991 and 2005.

Thirty-one isolates of bovine viral diarrhea virus (BVDV) isolated within the past 15 years from imported cattle by the Japanese Animal Quarantine Service (AQS) were used in this study in which a 5'-untranslated region of each isolate was genetically analyzed. Twenty-six of the 31 isolates were classified as BVDV1 and the remainder as BVDV2. Phylogenetic analysis of the RT-PCR fragments amplified from the isolates showed the presence of viruses belonging to the BVDV1a, BVDV1b, BVDV1c, unclassified BVDV1 genotypes, and BVDV2.

Relationship of bovine viral diarrhea virus persistent infection to incidence of diseases on dairy farms based on bulk tank milk test by RT-PCR.

The prevalence of bovine viral diarrhea virus (BVDV) in dairy herds in Hokkaido, Japan, was estimated by reverse transcription polymerase chain reaction (RT-PCR) using bulk tank milk samples. Sixteen out of 265 dairy herds were identified as BVDV positive, and at least one persistently infected (PI) cattle was recognized in each of the positive herds except for two herds of which, owners did not agree to examine individual cows. The proportion of positive herds with a history of BVDV PI was significantly higher than that with no history of BVDV PI (odds ratio (OR) 4.