Molecular analysis of the env, LTR, and pX regions of bovine leukemia virus in dairy cattle of Türkiye.

Bovine leukemia virus is a retrovirus that causes enzootic bovine leukosis and is associated with global economic losses in the livestock industry. The aim of this study was to investigate the genotype determination of BLVs from cattle housed in 6 different farms in Türkiye and the characterization of their LTR and pX (tax, rex, R3, and G4 gene) regions. For this purpose, blood samples from 48 cattle infected with BLV were used. The phylogenetic analysis based on the env gene sequences revealed that all BLVs were clustered in genotype 1 (G1), and the sequences of the LTR (n = 48) and the pX region (n = 33) of BLVs were obtained. Also, analysis of these nucleic acid and amino acid sequences allowed assessments similar to those reported in earlier studies to be relevant to transactivation and pathogenesis. This study reports the molecular analysis of the LTR and pX region of BLVs in Türkiye for the first time.

Isolation and genetic characterization of bovine ephemeral fever virus from epidemic-2020 in Turkey.

Bovine ephemeral fever virus (BEFV) infection occurs seasonally in many tropical and subtropical regions of Africa, Asia (including the Middle East), and Australia while it is exotic in Europe. In this study, the epidemiology of BEFV infection in Turkey that bridges southeastern Europe and Asia, geographically, was investigated according to the comparison of the nucleotide sequences of the virus caused the last epidemic in 2020 with those of the strains previously detected in Turkey as well as BEFV strains from other countries. In the phylogenetic analysis, based on an alignment of full-length G gene sequences, BEFVs from epidemic-2020 were located in Middle Eastern lineage and appear to represent most closely related BEFVs from India-2018 and 2019. The findings will contribute to a better understanding of BEFV epidemiology in Turkey.

Endless variety for bovine virus diarrhea viruses: new members of a novel subgroup into Pestivirus A from Turkey.

As ubiquitous pathogens, bovine virus diarrhea viruses (BVDVs) in cattle have been reported several times in Turkey. Over time, the frequency and importance of this infection has increased for the livestock industries. A total of 1291 animals were sampled from a dairy herd in Turkey suspected of BVDV clinical signs, for instance, reproductive failures (abortion, congenital malformations in calves, repeat breeding, etc.) and interdigital phlegmon in adult animals. Reverse transcription polymerase chain reactions (RT-PCRs) were made by using targeted 5' untranslated region (UTR), Npro, E2, and NS2-3 pestiviral gene region primers for antigen ELISA-positive samples (n = 20). The obtained amplicons were sequenced. Sequence results showed the presence of a new subgroup in Pestivirus A species. This paper describes the nucleotide sequences of a new BVDV 1 (BVDV 1-v) subgroup member.