Enhancement of the immune response and virological protection of calves against bovine herpesvirus type 1 with an inactivated gE-deleted vaccine.

Four immunisation protocols based on inactivated and attenuated commercially available marker vaccines for bovine herpesvirus type 1 (BHV-1) were compared. The first group of calves were vaccinated with an attenuated vaccine administered intranasally and an inactivated vaccine injected subcutaneously, four weeks apart; the second group were vaccinated twice with the attenuated vaccine, first intranasally and then intramuscularly; the third group were vaccinated twice subcutaneously with the inactivated vaccine; and the fourth group were vaccinated twice intramuscularly with the attenuated vaccine. A control group of calves were not vaccinated.

Production of bovine herpesvirus type 1-seronegative latent carriers by administration of a live-attenuated vaccine in passively immunized calves.

The consequences of the vaccination of neonatal calves with the widely used live-attenuated temperature-sensitive (ts) bovine herpesvirus type 1 (BHV-1) were investigated. The ts strain established acute and latent infections in all vaccinated calves either with or without passive immunity. Four of seven calves vaccinated under passive immunity became clearly BHV-1 seronegative by different serological tests, as did uninfected control calves after the disappearance of maternal antibodies, and they remained so for long periods.

Detection and genotyping of bovine diarrhea virus by reverse transcription-polymerase chain amplification of the 5' untranslated region.

A reverse-transcription polymerase chain reaction (RT-PCR) was developed to differentiate the bovine diarrhea virus (BVDV) from other pestiviruses, and to determine the genotype of the BVDV isolates. For this purpose, primer pairs were selected in the 5' untranslated region (5'UTR). The primers BE and B2 were located in highly conserved regions and were pestivirus-specific.

Assessment of the cell-mediated immunity in cattle infection after bovine herpesvirus 4 infection, using an in vitro antigen-specific interferon-gamma assay.

The cell-mediated immunity (CMI) following bovine herpesvirus 4 (BHV4) infection has been poorly investigated in cattle. The in vivo response measured by a delayed type of hypersensitivity (DTH) assay has been reported to be positive in only few animals showing serological evidences of BHV4 infection. We have investigated the CMI following BHV4 infection by an in vitro antigen-specific interferon gamma (IFN-gamma) release assay, as an indicator of an actively acquired immunity to BHV4.

Effect of repeated intradermal injections of bovine herpesvirus type 1 antigen on seronegative cattle.

Forty-three cattle seronegative to bovine herpesvirus-1 (BHV-1) were given from one to five intradermal injections of BHV-1 inactivated antigen at four-week intervals. This delayed hypersensitivity test was assessed by the increase in skin thickness. The activity of the antigen was assessed in five animals which had a previous natural BHV-1 infection with clinical signs and seroconversion.

Bovine herpesvirus 4 isolates: a comparison of three major glycoproteins.

Twenty-four Belgian field isolates of bovine herpesvirus 4 (BHV-4), together with four reference strains were compared by radio-immunoprecipitation and western blotting using a polyvalent antiserum and monoclonal antibodies raised against major glycoproteins. Most of these strains showed the same protein profile as the European reference strain Movar 33/63. For two strains the molecular weight of gp 6, p (gp 10/gp 17) and gp 10 were the same as those of the American reference strain DN 599.

Genomic diversity among bovine herpesvirus 4 field isolates.

Twenty-eight Belgian field isolates of bovine herpesvirus 4 (BHV-4) coming from a variety of clinical diseases have been studied by restriction analysis and Southern blot hybridization. The unique central part of the genome was very well conserved among strains; only one variation in a restriction site was detected in 3 isolates which contain an additional EcoRI site also present in the LVR 140 strain; three regions in the unique part of the genome varied in size, one of these was highly variable. The polyrepetitive fragments (prDNAs) situated in tandem at both genomic ends were also variable in size; most of the isolates exhibited prDNA units of one size (major prDNA) and some of them also contained prDNA units having a different size and present in a lower amount (minor prDNA) than the major prDNA.

The serological response to foot-and-mouth disease vaccination is not affected by simultaneous infectious bovine rhinotracheitis/adenovirus/parainfluenza 3 vaccination.

Young calves were simultaneously vaccinated by subcutaneous route against foot-and-mouth disease (FMD) and against infectious bovine rhinotracheitis/adenovirus/parainfluenza-3 (IBR/Adeno/PI-3) by intranasal route. The serological response against the 3 FMD virus types of the FMD vaccine was clearly positive. There was no significant difference between results of simultaneous FMD and IBR/Adeno/PI-3 vaccination and FMD vaccination only.

[Research on antibodies against BHV-1, BHV-2, BHV-4, BVD-MD virus, bovine adenovirus A and B, rotavirus and coronavirus in cattle in western Zaire: complementary results].

Two-hundred bovine sera from western Zaire were screened for antibodies to 8 viruses: BHV-1, BHV-2, BHV-4, BVD-MD virus, bovine adenovirus A and B, bovine rotavirus and bovine coronavirus. Positive sera were found to all these viruses. For animals whose origin was undoubted, the main features were the high prevalence of infections by rotavirus and BHV-4 and the low prevalence of infections by coronavirus and BVD-MD virus.

BHV4 (bovine herpes virus 4) related disorders in Belgian cattle: a study of two problem herds.

Two cattle farms, with a ten year history of BHV4 related postpartum metritis accompanied by fertility problems, were monitored during the winter season 1985-1986. BHV4 was isolated from the lochia from 55% of the animals on farm A and 66% of those on farm B. Respectively 59% and 30% of the animals presented postpartum metritis.

[Demonstration of BVD virus (bovine diarrhea virus) in many cell lines].

By specific fluorescent antibodies, it was shown that cell lines from bovine origin were contaminated with BVD virus. The same virus was also detected in cell lines from different species like horse, cat, monkey, rabbit, pig and sheep. The authors express their concern about the use of these cell lines as substrate for live virus vaccines.

[Experimental inoculation of bovine herpesvirus 4 (strain LVR 140) in pregnant and nonpregnant cows].

Ten cows (5 pregnant and 5 non pregnant) were inoculated with a BHV 4 (Bovine Herpes Virus 4) strain LVR 140. The infection caused metritis symptoms, but only after parturition and even if the calving occurred several weeks after the inoculation. The metritis was accompanied by leucopenia.

Prevalence of antibodies to bovid herpesvirus 1 (IBR-IPV), bovine virus diarrhoea, bovine respiratory syncytial parainfluenza 3, adeno A and adeno B viruses in indigenous and imported Moroccan cattle.

A serological survey on prevalence of antibodies to Bovid herpesvirus 1 (IBR-IPV) Bovine Virus Diarrhoea, Bovine Respiratory Syncytial, Parainfluenza 3, Adeno A and B viruses was performed in 524 cattle from different areas and management conditions in Morocco. General antibody prevalence was 62.8, 48.

[Evolution of anti-rota virus antibodies in the milk of cows treated in the last month of pregnancy either by adjuvated rotavirus vaccine or by the adjuvant fraction of the vaccine (author's transl)].

The authors describe the evolution of the secretion of anti-Rotavirus antibodies vaccine given three weeks before and repeated at the moment of parturition. Rota virus antibodies were detected at a high level during the three months test period with the Indirect Immunofluorescence Test, the seroneutralisation test and the immunofluorescence test. The four untreated animals excreted only rota-antibodies till day 6 .

Laboratory diagnosis methods for bovine respiratory syncytial virus.

Laboratory diagnosis of bovine respiratory syncytial (BRS) virus no longer poses a problem. Clinical diagnosis, based on signs of pulmonary emphysema manifest in autumn, should be confirmed by laboratory techniques. Direct isolation of the BRS virus from field samples in cell cultures is often unsuccessful, whereas detection of the viral antigens by staining ultra-thin tissue sections with fluorescein isothiocyanate antibody conjugates is highly effective.