Detection methods and characterization of bovine viral diarrhea virus in aborted fetuses and neonatal calves over a 22-year period

Abstract

Detection of bovine viral diarrhea virus (BVDV) in aborted fetus samples is often difficult due to tissue autolysis and inappropriate sampling. Studies assessing different methods for BVDV identification in fetal specimens are scarce. The present study evaluated the agreement between different diagnostic techniques to detect BVDV infections in specimens from a large number of bovine aborted fetuses and neonatal deaths over a period of 22 years. Additionally, genetic, serological, and pathological analyses were conducted in order to characterize BVDV strains of fetal origin. Samples from 95 selected cases from 1997 to 2018 were analyzed by antigen-capture ELISA (AgELISA), nested RT-PCR (RT-nPCR), and real-time RT-PCR (RT-qPCR). In addition, amplification and sequencing of the 5′UTR region were performed for phylogenetic purposes. Virus neutralization tests against the BVDV-1a, BVDV-1b, and BVDV-2b subtypes were conducted on 60 fetal fluids of the selected cases. Furthermore, the frequency and severity of histopathological lesions were evaluated in BVDV-positive cases. This study demonstrated that RT-nPCR and RT-qPCR were more suitable than AgELISA for BVDV detection in fetal specimens. However, the agreement between the two RT-PCR methods was moderate. The BVDV-1b subtype was more frequently detected than the BVDV-1a and BVDV-2b subtypes. Neutralizing antibodies to any of the three subtypes evaluated were present in 94% of the fetal fluids. Microscopically, half of the BVDV-positive cases showed a mild non-suppurative inflammatory response. These results emphasize the need to consider different methods for a diagnostic approach of BVDV associated to reproductive losses.

Frequency of bovine viral diarrhea virus (BVDV) in Argentinean bovine herds and comparison of diagnostic tests for BVDV detection in bovine serum samples: a preliminary study

“…All the strains identified were typed as BVDV-1 according to the primers designed by Gilbert et al [16]. Previous studies described that around 90% of the strains in Argentina were BVDV-1 [31][32][33][34]. Although type 2 was not identified in the tested samples, the primers used here were able to detect this BVDV type in Argentinean field isolates [34].…”

Development and Comparison of Cross-Linking and Non-Crosslinking Probe-Gold Nanoparticle Hybridization Assays for Direct Detection of Unamplified Bovine Viral Diarrhea Virus-RNA

“…Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, Flaviviridae family. Previously, BVDV was divided into two species of BVDV-1 and BVDV-2 based on genetic and antigenic differences [1]. However, recently, International Committee on Taxonomy of Viruses (ICTV) has reorganized the Pestivirus genus to eleven species, including Pestivirus A-K.…”

“…BVDV has a positive sense, the single-stranded RNA (ssRNA) genome, with an open reading frame (ORF) located between 5' and 3' untranslated regions (5'UTR, 3'UTR) [3]. BVDV causes diseases in ruminants, especially cattle [1]. Symptoms of BVDV infection in cattle include fever, diarrhea, abortion, stillbirth, congenital defective calf, decreased milk production, infertility, and even death.…”

“…One way to control the disease and prevent it from spreading is to detect and cull infected animals, especially PI animals. Several methods have been used for BVDV detection including virus isolation (VI), immunohistochemistry, antigen capture enzyme-linked immunosorbent assay (AC-ELISA), reverse transcriptase polymerase chain reaction (RT-PCR), and real-time RT-PCR [1,10]. VI is a "gold standard" diagnostic technique for BVDV (Sandvik, 2005); however, it is a labor-intensive and time-consuming process [10].…”

Development and Comparison of Cross-Linking and Non-Crosslinking Probe-Gold Nanoparticle Hybridization Assays for Direct Detection of Unamplified Bovine Viral Diarrhea Virus-RNA

“…Bovine viral diarrhea virus (BVDV) belongs to the Pestivirus genus, Flaviviridae family. Previously, BVDV was divided into two species of BVDV-1 and BVDV-2 based on genetic and antigenic differences [1].…”