Experimental infection of pregnant goats with bovine viral diarrhea virus (BVDV) 1 or 2

Abstract

Infections with bovine viral diarrhea virus (BVDV) of the genus pestivirus, family Flaviviridae, are not limited to cattle but occur in various artiodactyls. Persistently infected (PI) cattle are the main source of BVDV. Persistent infections also occur in heterologous hosts such as sheep and deer. BVDV infections of goats commonly result in reproductive disease, but viable PI goats are rare. Using 2 BVDV isolates, previously demonstrated to cause PI cattle and white-tailed deer, this study evaluated the outcome of experimental infection of pregnant goats. Pregnant goats (5 goats/group) were intranasally inoculated with BVDV 1b AU526 (group 1) or BVDV 2 PA131 (group 2) at approximately 25–35 days of gestation. The outcome of infection varied considerably between groups. In group 1, only 3 does became viremic, and 1 doe gave birth to a stillborn fetus and a viable PI kid, which appeared healthy and shed BVDV continuously. In group 2, all does became viremic, 4/5 does aborted, and 1 doe gave birth to a non-viable PI kid. Immunohistochemistry demonstrated BVDV antigen in tissues of evaluated fetuses, with similar distribution but reduced intensity as compared to cattle. The genetic sequence of inoculated viruses was compared to those from PI kids and their dam. Most nucleotide changes in group 1 were present during the dam’s acute infection. In group 2, a similar number of mutations resulted from fetal infection as from maternal acute infection. Results demonstrated that BVDV may cause reproductive disease but may also be maintained in goats.

Entry of Classical Swine Fever Virus into PK-15 Cells via a pH-, Dynamin-, and Cholesterol-Dependent, Clathrin-Mediated Endocytic Pathway That Requires Rab5 and Rab7

“…In order to assess whether CSFV entry is pH dependent, we first studied the effects of two lysosomotropic agents, chloroquine and NH 4 Cl, on CSFV infection in PK-15 cells. To ensure subtoxic doses of the drugs, cells were treated with 0 to 800 M chloroquine or 0 to 200 mM NH 4 Cl for 24 h, and cytotoxic effects were evaluated by a cell proliferation assay. As shown in Fig.…”

“…1A and B, cells tolerated up to 100 M chloroquine and 10 mM NH 4 Cl, respectively. Second, acridine orange staining was performed to confirm increasing pHs in intracellular vesicles following NH 4 Cl or chloroquine treatment. Untreated cells showed typical orange fluorescence, indicative of acidic compartments in PK-15 cells, whereas treated cells did not show an obvious pattern of fluorescence (Fig.…”

“…1C). Third, to test the effects of chloroquine or NH 4 Cl on the production of CSFV, cells were pretreated for 30 min with increasing concentrations of each compound, followed by inoculation with CSFV at a low MOI (0.05) for 1 h at 37°C. Viral replication was evaluated at 24 hpi by using RT-qPCR.…”

“…Data are presented as 2 Ϫ⌬⌬CT values from quadruplicate samples. To assess the effect of chloroquine and NH 4 Cl on the pH change of acidic intracellular vesicles, PK-15 cells treated with or without the compound for 1 h at 37°C were stained with acridine orange (1 mg/ml in DMEM without serum) for 15 min at 37°C. The cells were washed twice with phosphate-buffered saline (PBS) and then visualized with a Zeiss Axio Observer Z1 fluorescence microscope after 4=,6-diamidino-2-phenylindole (DAPI; Roche) staining.…”

Seroprevalence and risk factors for peste des petits ruminants and selected differential diagnosis in sheep and goats in Tanzania

“…capripneumoniae (Mccp) [10], FMD is caused by foot-and-mouth disease virus (FMDV) [11], and BT is caused by bluetongue virus (BTV) and is spread by the vector Culicoides mosquitos [12]. Infection with bovine viral diarrhoea virus (BVDV), or the closely related border disease virus (BDV), is generally not considered a differential diagnosis of PPR as these viruses mostly cause reproductive disease in small ruminants [13–15]. However, co-infections with PPRV and BVDV, BDV, or BTV are believed to exacerbate the clinical signs of PPR [16,17].…”