A Case Report: Evidence for Type 2 Bovine Viral Diarrhea Virus (BVDV)-Associated Disease in Beef Herds Vaccinated with a Modified-Live Type 1 BVDV Vaccine

Bovine viral diarrhea virus (BVDV) infection affects cattle throughout the world. It causes significant economic losses in the cattle industry. The potential for transmission of a cytopathic biotype of BVDV by in vivo-derived embryos has been thought to be negligible. However, there is no study to prove non-transmission of the most common field isolate of noncytopathic biotype (NCPB) of BVDV by IVF embryos. Here we report on the preliminary outcome of embryo transfer (ET) of IVF embryos exposed in vitro to type-1 (NY-1) and type-2 (P-131) genotypes of NCPB of BVDV. For this experiment, IVF embryos were generated using standard methods which briefly involve: maturation of cumulus–oocyte complexes in TCM medium, fertilization of oocytes with BVDV-free semen, and culture of zygotes to the blastocyst stage in SOF medium without somatic cells. Day 7 blastocysts were exposed for 1 h to NY-1 or P-131 (103–107 TCID50 mL–1) BVDV strains before being washed (without trypsin) as recommended by IETS. Two embryos were transferred on each occasion. Embryo recipients were virus-free and anti-BVDV antibody-free prior to ET. The recipients remained individually in isolation premises after ET. In total, 126 ET procedures were performed resulting in 57 pregnancies and 34 calves born free of the infectious virus and BVDV antibodies (5 pregnancies are still pending). In total, 23 pregnancies were lost after 30 days. Exposure of embryos to type-2 BVDV resulted in a loss of 46% (17/37) of pregnancies after 30 days post-ET and 20 recipients seroconverted to BVDV. Within seroconverted and pregnant animals (n = 14), only 2 recipients maintained pregnancy and delivered uninfected calves at term. In contrast, exposure of embryos to type-1 caused 30% (6/20) of the pregnancy losses after 30 days and did not cause any seroconversion in ET recipients. After washing, 33% (3/9) and 38% (17/44) single embryos from the infected pool of IVF embryos tested positive for the BVDV. In conclusion, under these experimental conditions, a proportion of recipients was apparently infected after receipt of BVDV-exposed embryos. However, all of the calves that survived to term were BVDV-free and anti-BVDV antibody free.

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Cross-protective efficacy of a bovine viral diarrhea virus (BVDV) type 1 vaccine against BVDV type 2 challenge

Vaccine ◽

10.1016/s0264-410x(98)00329-6 ◽

1999 ◽

Vol 17 (9-10) ◽

pp. 1117-1124 ◽

Cited By ~ 42

Author(s):

H.J Dean ◽

R Leyh

Keyword(s):

Bovine Viral Diarrhea Virus ◽

Protective Efficacy ◽

Bovine Viral Diarrhea ◽

Diarrhea Virus ◽

Viral Diarrhea ◽

Viral Diarrhea Virus

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DNA prime–protein boost strategies protect cattle from bovine viral diarrhea virus type 2 challenge

Journal of General Virology ◽

10.1099/vir.0.83251-0 ◽

2008 ◽

Vol 89 (2) ◽

pp. 453-466 ◽

Cited By ~ 31

Author(s):

R. Liang ◽

J. V. van den Hurk ◽

A. Landi ◽

Z. Lawman ◽

D. Deregt ◽

...

Keyword(s):

Bovine Viral Diarrhea Virus ◽

Neutralizing Antibodies ◽

Bovine Viral Diarrhea ◽

Diarrhea Virus ◽

Viral Diarrhea ◽

Cpg Oligodeoxynucleotide ◽

Protein Boost ◽

Viral Diarrhea Virus

At present, infections with bovine viral diarrhea virus (BVDV) type 2 occur nearly as frequently as those with BVDV type 1, so development of vaccines that protect cattle from both type 1 and type 2 BVDV has become critical. In this study, we compared various DNA prime–protein boost vaccination strategies to protect cattle from challenge with BVDV-2 using the major protective antigen of BVDV, glycoprotein E2. Calves were immunized with a plasmid encoding either type 1 E2 (E2.1) or type 2 E2 (E2.2) or with both plasmids (E2.1+E2.2). This was followed by a heterologous boost with E2.1, E2.2 or E2.1 and E2.2 protein formulated with Emulsigen and a CpG oligodeoxynucleotide. Subsequently, the calves were challenged with BVDV-2 strain 1373. All vaccinated calves developed both humoral and cell-mediated immune responses, including virus-neutralizing antibodies and IFN-γ-secreting cells in the peripheral blood. Depletion studies showed that CD4+ T cells were responsible for IFN-γ production. Furthermore, the calves vaccinated with either the E2.2 or the E2.1+E2.2 vaccines were very well protected from challenge with BVDV-2, having little leukopenia and showing no weight loss or temperature response. In addition, the animals vaccinated with the E2.1 vaccine were partially protected, so there was a certain level of cross-protection. These data demonstrate that a vaccination strategy consisting of priming with E2.2 or E2.1+E2.2 DNA and boosting with E2.2 or E2.1+E2.2 protein fully protects cattle from BVDV-2 challenge.

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Evaluation of protection against bovine viral diarrhea virus type 2 after vaccination of the calves with bovine viral diarrhea virus type 1 combo inactivated vaccine

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/1678-4162-11488 ◽

2020 ◽

Vol 72 (3) ◽

pp. 655-663

Author(s):

C. Chen ◽

Y. Liu ◽

H. Huang ◽

Q. Meng ◽

M. Xia ◽

...

Keyword(s):

Virus Type ◽

Rectal Temperature ◽

Bovine Viral Diarrhea Virus ◽

Bovine Viral Diarrhea ◽

Inactivated Vaccine ◽

Diarrhea Virus ◽

Viral Diarrhea ◽

Viral Diarrhea Virus

ABSTRACT This study was designed to evaluate the extent of the protection for bovine viral diarrhea virus type 2 (BVDV-2) infection, afforded by vaccination with a combo inactivated vaccine, which contains bovine viral diarrhea virus type 1 (BVDV-1) and infectious bovine rhinotracheitis virus (IBRV). Five 3-4-month-old calves were intramuscularly vaccinated with a single dose of the combo vaccine and boosted with same dose three weeks after the first vaccination, with five mock immunized calves serving as a control group. Twenty-one days after the second vaccination, all calves were challenged with BVDV-2 SX08 strain by spray into nostril. The unvaccinated animals developed typical clinical signs of high rectal temperature, diarrhoea with erosions and a dramatic drop in leukocyte counts. These signs occured markedly less in all vaccinated animals, the rectal temperature, leukopenia and virarmia of which, were significantly less than the mock immunized calves. It can be concluded that vaccination with the combo inactivated vaccine affords cross-protection against clinical effects of a challenge-infection with BVDV-2 SX08 strain, although it was part protection.

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