Proteins Specified by bovine herpesvirus 1 (infectious bovine rhinotracheitis virus)

An electrophoretic analysis of radioactively labeled, purified, "empty" and DNA-containing infectious bovine rhinotracheitis virions revealed the presence of 25 to 33 structural (virion) polypeptides. A total of 11 of these polypeptides could be labeled with [3H]glucosamine and were identified as glycoproteins. In addition to the 25 structural polypeptides, infectious bovine rhinotracheitis virus infected cells also contained at least 15 nonstructural (nonvirion) polypeptides that were not present in purified virions. Expression of the viral polypeptides in infected cells was controlled temporally. Thus, most viral polypeptides could be categorized as "alpha" (immediate early), "beta" (early), or "gamma" (late) on the basis of their order of appearance in infected cells and whether their syntheses were dependent upon prior viral protein or DNA synthesis. None of the glycoproteins belongs to the alpha class, although at least one (GVP11) was synthesized in the absence of viral DNA synthesis. Serum from a cow in which infectious bovine rhinotracheitis virus lesions were reactivated by dexamethasone precipitated both structural and nonstructural polypeptides.     

Prevalence of antibodies to IBR and BVD viruses in dairy cows with reproductive disorders

We determined the prevalence of antibodies to infectious bovine rhinotracheitis virus (IBRV) and bovine viral diarrhea virus (BVDV) in sera of dairy cows on 4 different farms in the Republic of Croatia. A high percentage (60.8%) of cows had various reproductive disorders. The results showed that seroprevalence of infectious bovine rhinotracheitis (IBR) was 85.8% and that of bovine viral diarrhea (BVD) was 79.2% in tested cows. Antibodies to both viruses were found in 80.8% of cows with reproductive disorders but in only 46.8% of cows without reproductive disorders. This difference was statistically significant (P<0.01), and indicated a connection between reproductive disorders and simultaneous infections with IBR and BVD viruses in dairy cows.     

Identification of a herpesvirus isolated from cytomegalovirus-transformed human cells.

Human cells transformed by cytomegalovirus and transplanted to athymic nude mice yielded a cytopathic virus, Hershey Medical Center virus, following prolonged in vitro passage of the tumor cells. The virus is a double-enveloped herpesvirus, is sensitive to ether, and is inhibited by iododeoxyuridine. No significant antigenic relationship to herpes simplex virus was detected using herpes simplex virus-immune sera in neutralization and immunofluorescence tests, but indirect immunofluorescence tests revealed cytomegalovirus-related antigenicity. Further immunological tests revealed that Hershey Medical Center virus is antigenically indistinguishable from infectious bovine rhinotracheitis virus. Thus, it appears that Hershey Medical Center virus is infectious bovine rhinotracheitis virus, which presumably appeared in the cell culture as a contaminant from fetal calf serum.     

Significance of Neospora caninum in British dairy cattle determined by estimation of seroprevalence in normally calving cattle and aborting cattle

A case control study was conducted to evaluate the significance of Neospora caninum infections in cattle in England and Wales. The prevalence of N. caninum in normally calving cattle (the control group; n = 418) and aborting cattle (n = 633) was estimated using a commercial antibody-detection ELISA. Prevalence estimates for bovine virus diarrhoea virus, infectious bovine rhinotracheitis virus and Leptospira hardjo were also obtained by serology. The prevalence of N. caninum was significantly higher (P < 0.0001) in the aborting group (18%; 95% confidence interval: 15%, 21%) than in the control group (6%; 95% confidence interval: 4%, 8%); the latter is the first estimate, to date, of the national seroprevalence of N. caninum in dairy cattle in England and Wales. Prevalence estimates for bovine virus diarrhoea virus, infectious bovine rhinotracheitis virus and L. hardjo were not found to be higher in the aborting cattle than in the control group. With N. caninum, a strong association between seropositivity and abortion was found, with seropositive cows being 3.5-times more likely to abort than seronegative cows (odds ratio = 3.49; 95% confidence interval: 2.16, 5.69). Furthermore, 12.5% of abortions in dairy cattle in England and Wales may be attributable to N. caninum, as indicated by estimation of the population aetiological fraction.     

Notices

A virus isolated from the lung of an aborted Hereford fetus was shown to possess the physical and chemical properties of the herpesvirus group. The virus designated bovine herpesvirus (BH-1247) was isolated in cultures of Madin-Darby bovine kidney (MDBK) and primary bovine embryonic kidney (BEK) cells. Electron microscopic studies revealed typical forms of virus particles of the herpesvirus group. The virus was sensitive to chloroform and virus replication was inhibited by the addition of 5-iododeoxyuridine into the cell culture medium. The characteristic features of the cytopathic changes were syncytial formations with intranuclear inclusion bodies. Discrete plaques were formed in MDBK cell cultures overlaid with agar. Virus growth studies in BEK cells revealed infectious virus to be cell associated and replicated at low titer. By serum neutralization tests the virus was shown to be distinct from bovine herpesviruses; infectious bovine rhinotracheitis, DN-599, Movar 33/63, bovine mammallitis, malignant catarrhal fever and feline viral rhinotracheitis, equine herpesvirus I and pseudorabies. The isolate was nonpathogenic to mice inoculated subcutaneously, intracerebrally and intraperitoneally. Virus replication was not demonstrated when inoculated on the chorioallantoic membrane of embryonated eggs.     

Prevalence of infectious agents in free-ranging white-tailed deer in northeastern Mexico

The objectives of this study were to determine the prevalence of antibodies against brucellosis, leptospirosis, infectious bovine rhinotracheitis virus, and bovine viral diarrhea virus (BVDV) in white-tailed deer (Odocoileus virginianus) in northeastern Mexico. Deer (n=521) were captured from helicopter using a netgun on 15 ranches covering 62,114 ha in the states of Coahuila, Nuevo Leon, and Tamaulipas during spring 2004. The prevalence of antibodies against Leptospira, infectious bovine rhinotracheitis, BVDV, and brucellosis were 5.6, 41.1, 63.5, and 0%, respectively, indicating that white-tailed deer and cattle may share disease agents when cohabiting in northeastern Mexico.     

Trypsin treatment of bovine embryos after in vitro exposure to infectious bovine rhinotracheitis virus or bovine herpesvirus-4

The objectives of this study were to evaluate the efficacy of trypsin treatment for the removal/inactivation of infectious bovine rhinotracheitis virus (IBRV) adhering to zona pellucida-intact (ZP-I) bovine embryos and to determine if bovine herpesvirus-4 (BHV-4) adheres to ZP-I bovine embryos. When adherence of BHV-4 was demonstrated, an additional objective was to determine whether trypsin treatment removes or inactivates this virus. A total of 139 ZP-I embryos was collected from superovulated donor cows at 7 d after estrus. Embryos were exposed to 10(6) to 10(7) plaque-forming units (pfu) of either IBRV or BHV-4 for 1 to 2 h. Subsequently, approximately equal numbers of embryos exposed to each virus were either washed 12 times and the washes and embryos examined for the presence of infectious virus, or they were treated with trypsin and the embryos examined for the presence of infectious virus. Although the fourth wash was the last positive wash, an average of 18 pfu of virus was detected from each of six groups (a total of 24 embryos) after exposure to IBRV and washing. Infectious bovine rhinotracheitis virus was not isolated from any of nine trypsin-treated groups (a total of 43 embryos). The seventh wash was the last positive wash for any group after exposure to BHV-4, yet an average of 2 pfu of virus was detected from each of six groups (a total of 29 embryos) after washing. No BHV-4 was isolated from any of eight trypsin-treated groups (a total of 43 embryos). The study confirmed previous reports that IBRV adheres to the bovine ZP after in vitro exposure and that trypsin treatment is effective in keeping ZP-I embryos free of this virus. Adherence of BHV-4 to ZP-I bovine embryos was demonstrated for the first time. Trypsin treatment was also effective in removing this herpesvirus.     

Serologic survey for selected microbial pathogens in bison from Kansas.

A serologic survey was conducted on an American bison (Bison bison) herd in Kansas for antibodies against Brucella spp., Leptospira interrogans serovar canicola, pomona, grippotyphosa, icterohaemorrhagiae, and hardjo, Anaplasma spp., bluetongue virus, infectious bovine rhinotracheitis virus and bovine viral diarrhea virus. There was an increase in prevalence of bluetongue antibodies from 38% in 1987 to 100% in 1989 in animals greater than or equal to 24-mo-old. Prevalences of antibodies against the other livestock pathogens were either negative or at levels associated with previous vaccination.     

Mitogen- and antigen-responsive milk lymphocytes.

Bovine and canine milk contained lymphocytes that responded to the nonspecific mitogens; phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM) and gram negative bacterial lipopolysaccharide (LPS). It also was found that animals specifically sensitized with tuberculin or infected with infectious bovine rhinotracheitis virus (IBR) had antigen sensitive lymphocytes in their milk. In general, the responses of the milk lymphocytes from an individual animal were not identical to responses for the blood lymphocytes. Marked variation was observed in the daily responses of cells from milk samples from different quarters of the same animal, and between animals. The implications of antigen and mitogen responsive milk lymphocytes are discussed, in relation to their possible role in protective immunity.     

Microtiter Tests for Detecting Antibody in Bovine Serum to Parainfluenza 3 Virus, Infectious Bovine Rhinotracheitis Virus, and Bovine Virus Diarrhea Virus

Microneutralization tests for detection of antibody in bovine serum to three bovine viruses are described. The Madin-Darby bovine kidney cell line was used with parainfluenza 3 virus (PI 3), whereas serially cultivated bovine embryonic kidney cells were used for infectious bovine rhinotracheitis virus and bovine virus diarrhea virus. Comparison of micro-hemagglutination-inhibition (HI) with micro-serum-neutralization (SN) tests for PI 3 showed the SN test to be more sensitive, more specific, and therefore more useful than the HI test for detecting antibody. Although the effect of trypsin-periodate treatment of serum was to reduce the HI titer of numerous sera by a twofold dilution, sufficient evidence could not be found to indicate that nonspecific HI inhibitors to PI 3 are present in bovine sera.     

Single Pathogen Challenge with Agents of the Bovine Respiratory Disease Complex

Bovine respiratory disease complex (BRDC) is an important cause of mortality and morbidity in cattle; costing the dairy and beef industries millions of dollars annually, despite the use of vaccines and antibiotics. BRDC is caused by one or more of several viruses (bovine respiratory syncytial virus, bovine herpes type 1 also known as infectious bovine rhinotracheitis, and bovine viral diarrhea virus), which predispose animals to infection with one or more bacteria. These include: Pasteurella multocida, Mannheimia haemolytica, Mycoplasma bovis, and Histophilus somni. Some cattle appear to be more resistant to BRDC than others. We hypothesize that appropriate immune responses to these pathogens are subject to genetic control. To determine which genes are involved in the immune response to each of these pathogens it was first necessary to experimentally induce infection separately with each pathogen to document clinical and pathological responses in animals from which tissues were harvested for subsequent RNA sequencing. Herein these infections and animal responses are described.     

Enhancement by levamisole of the contractions induced by prostaglandin E2 in the guinea-pig isolated ileum

The effect of levamisole on prostaglandin E₂ (PGE₂)-evoked contractions was studied on guinea-pig isolated ileum. Addition of levamisole (10 μg/ml) to the organ bath produced a pronounced increase in the amplitude of the PGE₂-evoked responses. Levamisole (10 μg/ml) also sensitized the guinea-pig isolated ileum to 5-hydroxytryptamine and bradykinin, but not to histamine. The effect of the levamisole was not due to stimulation of autonomic ganglia or cholinergic activity since it was unaffected by hexamethonium or atropine, but it was prevented by indomethacin.     

Diagnosis of rotavirus, adenovirus, and herpesvirus infections by immune electron microscopy using a serum-in-agar diffusion method

The sensitivity of immune electron microscopy (IEM) for the detection and identification of bovine rotavirus, infectious bovine rhinotracheitis virus (IBR), and canine adenovirus has been studied by using the serum-in-agar (SIA) method in which a specific antiserum has been incorporated in agar.     

The use of polyethylene glycol in concentration and purification of several bovine viruses.

The polyethylene glycol (PEG) precipitation method was used for the concentration and purification of eight bovine viruses. Good results were obtained from four viruses, parainfluenza--3 virus, bovine enterovirus, bovine adenovirus, and bovine parvovirus. No satisfactory results of concentration were obtained from bovine reovirus, bovine viral diarrhea virus, and infectious bovine rhinotracheitis virus. The failure of concentration of the four viruses seems to be ascribed rather to the resuspending of virus from the virus--PEG precipitate than to the precipitation of virus from infective culture fluid. This method can be applied as the initial step to the concentration of parainfluenza--3 virus, bovine enterovirus, bovine adenovirus, and bovine parvovirus from a large volume of material, since it is simple, rapid, and inexpensive.     

Influence of Relative Humidity on the Survival of Some Airborne Viruses

A system for studying the effects of relative humidity (RH) and temperature on biological aerosols, utilizing a modified toroid for a static aerosol chamber, is described. Studies were conducted at 23 C and at three RH levels (10, 35, and 90%) with four viruses (Newcastle disease virus, infectious bovine rhinotracheitis virus, vesicular stomatitis virus, and Escherichia coli B T3 bacteriophage). Virus loss on aerosol generation was consistently lower at 90% than at 10 or 35% RH. When stored at 23 C, Newcastle disease virus and vesicular stomatitis virus survived best at 10% RH. Infectious bovine rhinotracheitis virus and E. coli B T3 bacteriophage survived storage at 23 C best at 90% RH.     

Health evaluation of pampas deer (Ozotoceros bezoarticus celer) at Campos del Tuyú Wildlife Reserve, Argentina

Samples from 14 free-ranging pampas deer (Ozotoceros bezoarticus celer) were collected in 1995 and 1998, at Campos del Tuyú Wildlife Reserve, Buenos Aires, Argentina. Hematology, serum chemistries, minerals and metals, and fecal parasites were analyzed. In addition, fecal ova and parasites were evaluated seasonally during 1998-2000. Serology for infectious diseases included blue-tongue, brucellosis, bovine respiratory syncytial virus infection, bovine viral diarrhea/mucosal disease, infectious bovine rhinotracheitis, Johne's disease (paratuberculosis), foot and mouth disease (FMD), leptospirosis (eight serovars), epizootic hemorrhagic disease, and parainfluenza-3 (PI-3). Three (21%) pampas deer had antibodies to Leptospira spp. and six (43%) to PI-3 virus. Serologic results for all other infectious agents were negative. Domestic cattle (n = 27) included in this study for comparison had antibodies to Leptospira, infectious bovine rhinotracheitis virus, bovine viral diarrhea virus, and PI-3 virus (74-100% of tested animals) and one animal (4%) to Brucella sp. All cattle had antibodies to FMD virus attributable to vaccination. This study provides the first data on the health status of the southernmost sub-species of pampas deer.     

Antibodies to bovine bacterial and viral pathogens in pronghorns in Alberta, 1983

Sera from 210 pronghorns (Antilocapra americana) ranging in southeastern Alberta were tested for antibodies to disease agents present in indigenous cattle. No antibodies to Brucella abortus, Leptospira interrogans serovars pomona, hardjo, or grippotyphosa, or infectious bovine rhinotracheitis virus were found. Antibodies at prevalences of 43.8% and 49.2% were detected to bovine virus diarrhea (BVD) and parainfluenza type 3 (PI-3) viruses, respectively. The much higher prevalence of BVD virus antibodies in cattle than in pronghorns, and the occurrence of clinical bovine PI-3 infection in the study area, suggest that cattle may be a source of infection to the pronghorns.     

Method for Studying Particle Size and Infective Potential of Infectious Bovine Rhinotracheitis Virus Aerosols

A technique is described for estimating the number of potential respiratory infectious loci of aerosolized infectious bovine rhinotracheitis virus.     

Observations on the epidemiology of the herpesvirus of infectous bovine rhinotracheitis/infectious pustular vulvovaginitis in wildebeest.

Spontaneous vulvovaginitis erupted in wildebeest (Connochaetes taurinus) after betamethasone inoculation. Infectious bovine rhinotracheitis/infectious pustular vulvovaginitis (IBR/IPV) is probably a venereal disease because virgin wildebeest did not develop vulvovaginitis after betamethasone injections, nor was the virus transmitted to these virgin wildebeest and steers which were in pen contact with the affected animals. A domestic bovine heifer developed mild IPV and became a virus carrier, when exposed to the wildebeest IPV virus by vaginal instillation.