Bovine Viral Diarrhea-mucosal Disease Research Articles

Induction of mucosal disease in cattle persistently infected with noncytopathic bovine viral diarrhea-mucosal disease virus by superinfection with cytopathic bovine viral diarrhea-mucosal disease virus.

Three head of cattle persistently infected with noncytopathic bovine viral diarrhea-mucosal disease virus (ncBVD-MDV) were superinfected naturally or experimentally with cytopathic bovine viral diarrhea-mucosal disease virus (cBVD-MDV). In the naturally superinfected case, one animal manifested pyrexia and severe diarrhea, and died without developing antibodies to cBVD-MDV. However, another animal survived with only continual slight anorexia and pyrexia, and developed strong resistance to the superinfected strain. In the experimental cases, induction of MD was unsuccessful in two persistently infected cattle when superinfected with cBVD-MDV antigenically heterologous for persistently infected ncBVD-MDV. They also developed antibodies to the cBVD-MDV strain with which they had been infected. After 6 months, these cattle were infected again with a cBVD-MDV strain different from that used in the previous experiment. One animal infected with this strain, which was antigenically homologous to the persistently infected strain, died after developing MD symptoms without developing antibodies to the infecting strain. It is suggested that the antigenic relationship between the persistent ncBVD-MDV and the superinfected cBVD-MDV was an important factor in developing MD.

牛ウイルス性下痢-粘膜病の5例

牛ウイルス性下痢-粘膜病の5例

Bovine virus diarrhoea-mucosal disease and border disease in Egypt.

In Egypt, bovine virus diarrhoea-mucosal disease (BVD-MD) was initially detected as the result of a serological survey of cattle and sheep, using the serum neutralisation test. In 1970, the causal pestivirus was isolated from bovine calves and buffalo calves with pneumonia and enteritis. Mixed viral infections were also prevalent. Cases of immune tolerance were identified. The Egyptian industry had complained of unthrifty cattle and high death rates of bovine calves and buffalo calves. A rinderpest outbreak in 1982 involved some cattle and buffalo which had been vaccinated against the disease, and such animals were positive to the gel diffusion test for BVD-MD pestivirus. Extensive immunosuppression due to BVD MD virus was suspected, because the attenuated cell-culture vaccine against rinderpest, issued in Egypt since 1965, had not been tested for freedom from non-cytopathic BVD-MD virus. Experimental infection of susceptible sheep with BVD-MD virus resulted in symptoms of Border disease. Innocuity of the attenuated C24V bovine pestivirus vaccine for animal tissues and the immune system of calves was confirmed.

Diabetes Mellitus in Cattle Infected With Bovine Viral Diarrhea Mucosal Disease Virus

Diabetes in cattle has various etiologies1. In humans, virus-induced insulin dependent diabetes mellitus (IDDM) has been reported. It has also been reported that cattle infected with foot-and-mouth disease contracted diabetes mellitus2. Craighead and coworkers observed experimental diabetes in mice after inoculation of encephalomyocarditis virus3. Other viruses suspected of inducing diabetes are coxsackie, mumps, rubella and cytomegalo virus4.
 Bovine viral diarrhea mucosal disease (BVD-MD) is a frequently fatal infectious disease of cattle. There is no concrete evidence to date that BVD-MD virus induces diabetes. In this report, the clinicopathological characteristics of diabetes mellitus in cattle were described, and the relationship between BVD-MD and diabetes mellitus was discussed.

Diabetes mellitus in cattle infected with bovine viral diarrhea mucosal disease virus.

Four Japanese black cattle and four Holstein-Friesian cows were diagnosed with diabetes mellitus. Based on intravenous glucose tolerance tests, all these animals were believed to be insulin-dependent diabetics. Moreover, bovine viral diarrhea-mucosal disease (BVD-MD) virus was isolated and mucosal lesions and diarrhea were recognized in all cases. There was no genetic relation among the affected cattle. The breeding places of these cattle were different to each other. Therefore, it is suggested that BVD-MD virus induced the diabetes mellitus.

Sero-prevalences of selected cattle diseases in the Kafue flats of Zambia.

Sera from five traditionally managed herds grazing in the Kafue flats were tested for antibodies to bovine viral diarrhoea-mucosal disease (BVD-MD), parainfluenza 3 (PI3), infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV), bovine adenovirus 3 (BAV3) and Bluetongue (BT). The sero-prevalences of the first four diseases were respectively 76.2, 94.4, 42.1 and 87.4%. Five samples (2.3%) gave doubtful reactions for BT. Prevalences of 28.5% for brucellosis, 14% for Rift Valley fever (RFV), 0.9% for Q fever and 11.2% for chlamydiosis were also recorded. Significantly higher values for BVD-MD (p<0.005), IBR-IPV (p<0.01) and brucellosis (p<0.05) were found in animals over 1 year of age. No differences were recorded between herds or between male and female animals.The high concentration of wild and domestic ruminants grazing together in the flood plains during the dry season may be a major determinant of the high values observed. Traditional farmers, slaughterhouse workers and other people involved in livestock production are particularly at risk of contracting brucellosis and RVF because of the high prevalences in cattle and local habits favourable to their transmission.

Seroprevalence of bovine viral diarrhea/mucosal disease in southern Chile

The seroprevalence of bovine viral diarrhea/mucosal disease (BVD/MD) was estimated using the serum neutralization technique on 948 cow serum samples collected from 40 large herds of the IXth and Xth Regions in southern Chile. In addition, 116 bulls were tested. The seroprevalence was found to be high, with 700 of the 948 cows testing positive (73.8%) at a titer of ⩾1:5. The herd seroprevalence was 100%, with all the herds studied containing at least one positive animal. The seroprevalence in bulls was 81.0%. The survey indicated a high seroprevalence throughout the study area, with a maximum of 87.4% in the province of Cautin, IXth Region. Furthermore, the prevalence of reactors was high in animals managed in extensive production systems and there were no differences in prevalence observed between beef, dairy and mixed farming. The results indicate that BVD/MD is widely distributed in the adult bovine population of large herds in southern Chile.

Current situation of bovine virus diarrhoea-mucosal disease (BVD-MD) virus infections and their antigenic diversity in Hokkaido, Japan

The current situation of bovine virus diarrhoea-mucosal disease (BVD-MD) virus infections is briefly reviewed, with special reference to problems arising from fetal infection in the Hokkaido district, a northern island of Japan. The results of some investigations on BVD-MD virus carried out in Japan are also described. Although bovine congenital anomalies caused by BVD-MD virus and mucosal disease may be late sequelae to fetal infection and occur sporadically, it appears that their incidence and importance in the Hokkaido district have increased in recent years. The results of antigenic characterisation of the recent isolates and serologic survey on bovine sera suggested that BVD-MD viruses with various antigenic properties are widespread among cattle in the district. There is also a possibility that clinical manifestations in infected cattle may differ with the antigenicity of the viruses. In addition, the virological investigations on experimental and naturally occurring mucosal disease suggested that persistently infected cattle are populations at high risk of developing mucosal disease. The antigenic homology of non-cytopathogenic persistent virus and cytopathogenic virus is probably an important factor in the pathogenesis of mucosal disease.

Bovine virus diarrhoea-mucosal disease : prevalence, epizootiology and control measures in the USSR

Bovine virus diarrhoea-mucosal disease was described for the first time in the USSR in 1967. The disease occurs in 20 to 80% of farms, depending on geographic and climatic zones of the country. Control measures against the disease include quarantine restrictions and prevention by means of specific preparations of active and passive effect. Passive prophylaxis is conducted by aerosol methods for groups and individuals.

Incidence, epidemiology and control of bovine virus diarrhorea virus in South America

Outbreaks of diarrhoea associated with mucosal erosions of the mouth, tongue and digestive tract, clinically diagnosed as bovine virus diarrhoea-mucosal disease (BVD-MD), have been reported in Argentina and Brazil since the 1960's. However, primary isolation of the virus of BVD-MD is fairly recent, occurring in 1974 for Brazil, 1984 for Argentina, 1985 for Chile and 1981 for Colombia. In Argentina both cytopathogenic and non-cytopathogenic BVD virus strains have been identified. Elsewhere in South America this differentiation does not seem to have been carried out. Serological surveys have confirmed the existence of BVD virus infection in six countries (Argentina, Brazil, Chile, Colombia, Peru and Uruguay), with an incidence rate ranging between 37 and 77% of cattle in the areas surveyed. Diarrhoea in calves between 3 and 18 months of age, often associated with mucosal erosions, has been the most commonly observed syndrome. In some cases an upper respiratory tract involvement was described. In one epizootic, in the Sabana de Bogota plateau of Colombia, reproductive failure associated with abortions or birth of weak calves was the main clinical syndrome.

The diagnosis of bovine virus diarrhoea-mucosal disease in cattle

Laboratory diagnostic procedures for bovine virus diarrhoea and mucosal disease are reviewed. For serology, emphasis is placed on the virus neutralisation test and enzyme immunoassays. The techniques and the pitfalls which may be encountered in culture procedures for isolation of the virus are described, with special reference to the use of immunofluorescence and immunoperoxidase methods for the detection of non-cytopathogenic virus strains. Viral antigen may also be detected directly in clinical or pathological samples. Monoclonal antibodies are expected to play an increasing role in diagnostic tests, and the application of gene probes for virus detection is anticipated in future years. In the interpretation of diagnostic laboratory test results, the importance is stressed of reviewing them in the context of the herd disease and breeding history, and relating them to current understanding of the pathogenesis and epidemiology of the disease.

牛ウイルス性下痢・粘膜病生ワクチンの乳牛における抗体応答と胎子感染

The antibody response and possibility of fetal infection were assessed in cows that had been vaccinated with a bovine viral diarrhea-mucosal disease live virus vaccine (No.12-43 strain). The seroconversion rate was examined in 92 vaccinated cows. In those cows which had antibody titer of 4 or lower at the time of vaccination, the seroconversion rate reached almost 100%, while in those with antibody titer of 8 or higher, the rate tended to be lower in the cows which showed higher antibody levels against the No.12 and Nose strains. Twenty-six antibody-negative cows were vaccinated and their antibody titers were determined two months later. The mean antibody titers (n=26) against the No.12, Nose, and KS86-1 strains were 4806.5, 1170.0, and 121.4, respectively. Rises in antibody titer were also recognized against field-isolated virus strains obtained from cattle in Hokkaido, and the mean antibody titers against three isolates were 460.2, 135.0, and 131.5. The mean antibody titer (n=6) determined one year after the vaccination was 512 against the No.12 and Nose strains, and 64 against the K (+) strain. In some cases, however, in spite of a high antibody level against the KS86-1 strain, a significant rise in antibody titer was recognized when antibody levels against the No.12 and Nose strains were low. This suggested that some field strains may greatly be different serologically from vaccine strains.Eight antibody-negative pregnant cows were vaccinated, and all of them showed a significant rise in antibody titer after vaccination. Furthermore, antibody to the No.12 strain was detected in 5 pre-colostrol calves born to these 8 cows, suggesting fetal infection.The present findings indicated that the live virus vaccine used in this study induced an antibody response effective enough for prevention of bovine viral diarrhea-mucosal disease, although the use for pregnant cows should be avoided.

Antigenic diversity of bovine viral diarrhea-mucosal disease(BVD-MD) viruses recently isolated from persistently infected cattle and mucosal disease, and serologic survey on bovine sera using antigenically different BVD-MD viruses.

Twenty nine recent isolates of bovine viral diarrhea-mucosal disease (BVD-MD) virus, 17 from persistently infected cattle and 12 from mucosal disease, were compared antigenically with the reference strains by a serum neutralization test. The reference viruses were divided into 2 groups, tentatively designated as N and K, based on the antigenic relationships in the cross-neutralization test. Antigenic properties of recent isolates were considerably different with the sources of virus isolation. Seventeen isolates recovered from persistently infected cattle were divided into 3 groups in the neutralization test using antisera to the reference strains; 12 and 2 were considered as the possible members of groups K and N, respectively, and the others belonged to neither group. On the other hand, 10 of 12 isolates recovered from mucosal disease were considered as the possible members of group N, and the others were classified into neither group. Interestingly, none of BVD-MD viruses isolated from cases of mucosal disease belonged to group K. The results of serologic survey on sera collected from 713 cattle at the Hokkaido provinces in 1974 to 1988 indicated that infections of cattle with BVD-MD viruses other than group K were prominent before 1981. Cattle infected with group K BVD-MD virus were first detected in 1982, and increased in number thereafter. The results obtained in this study suggested that BVD-MD viruses with various antigenic properties spread widely among cattle herds, and also a possibility that clinical manifestations in cattle infected with BVD-MD viruses may differ with their antigenic properties.

黒毛和種肥育牛に見られた牛ライノウイルス感染症

There was an outbreak of an acute respiratory disease in cattle in Nagasaki Prefecture in March, 1987. The 45 cattle, all from different places in Nagasaki Prefecture from outsideof the prefecture, involved in the outbreak showed fever, coughing, nasal discharge, labored breathing and diarrhea five days after they were introduced and five of them died.Pasteurella haemolytica was isolated from six nasal swab specimens in seven ill cattle (85.7%). Mycoplasma SP. was isolated from two of seven specimens (28.6%). Two cytopathogenic virus strains were isolated in MDBK cell cultures from nasal swabs of cattle with markedleukopenia.The isolants were readily inactivated by acid and heating at 50°C for 30 minutes, but they resisted chloroform. The type of their nucleic acid was determined to be RNA. Immunoelectron microscopy using convalescent serum revealed picornavirus-like particles in cultured material.The isolants were neutralized with antiserum against the Sd-1 strain of bovine rhinovirus type 1.A significant rise in antibody titer was shown against the isolants in convalescent serum of the ill cattle, but not against bovine respiratory syncytiai virus, bovine adenovirus type 7, or bovine entero virus. A small rise in antibody titer against bovine herpesvirus type 1, parainfluenza virus type 3 and bovine viral diarrhea mucosal disease virus, was shown. It is considered, however, that such a sero-conversion may be due to vaccination of combined vaccine against these viral agents.Serologic survey against the isolated virus in sera collected from 195 cattle in 1987 in Nagasaki Prefecture revealed that 73. 5% of those over one year old were antibody positive, while 29. 9% of those from four to 10 months old particulaly have a tendency to show a low positive rate.

北海道の石狩地区における牛ウイルス性下痢・粘膜病 (BVD・MD)

北海道の石狩地区における牛ウイルス性下痢・粘膜病 (BVD・MD)

Serological comparison of cytopathogenic and non-cytopathogenic bovine viral diarrhea-mucosal disease viruses isolated from cattle with mucosal disease.

Ten cattle that died with mucosal disease were examined for bovine viral diarrhea-mucosal disease (BVD-MD) viruses. Both cytopathogenic (CP) and non-cytopathogenic (NCP) BVD-MD viruses were isolated concomitantly from 9 of them, and only a CP virus was recovered from the other. Then each pair of CP and NCP viruses was compared serologically by a serum neutralization test. Each pair of CP and NCP viruses from the same cattle was found to be serologically indistinguishable, although a minor antigenic difference was observed among the groups of the paired viruses. These results seem to support the hypotheses that mucosal disease occurs in persistently infected cattle which were induced by in utero infection with NCP virus when they are superinfected with CP virus, and the antigenic homology in CP and NCP BVD-MD viruses may be an important factor in the pathogenesis of the disease.

Serological characterization of viruses isolated from experimental mucosal disease

Four cattle persistently infected with non-cytopathogenic bovine viral diarrhoea-mucosal disease (BVD-MD) virus and 3 normal controls were challenge exposed to cytopathogenic BVD-MD viruses that are antigenically different from the persistent viruses. Two of the persistently infected cattle developed mucosal disease and became moribund on postinoculation days (PID) 28 and 14, respectively; one developed severe and chronic diarrhoea and became moribund on PID 32; and the other remained healthy until the end of the experiment (PID 150). ll control cattle showed transient fever, but no diarrhoea, and recovered from infection. Cytopathogenic viruses were isolated from blood of all cattle early in infection (PID 5–10) and from carcasses at necropsy. The former viruses were antigenically identical with the challenge viruses. On the other hand, the antigenicity of the cytopathogenic viruses isolated from carcasses at necropsy were different from that of the challenge viruses but similar to that of the non-cytopathogenic persistent viruses. Three of 4 persistently infected cattle, but not the calf which became moribund on PID 14, produced serum neutralizing (SN) antibodies to the challenge viruses, but not to the persistent viruses and the cytopathogenic viruses isolated from carcasses at necropsy. Control cattle produced SN antibodies to both the challenge and persistent viruses.

A rapid, quantitative assay for titration of bovine virus diarrhoea-mucosal disease virus

An end point dilution microtitration assay is described that can be used for the titration of both cytopathic and non-cytopathic isolates of bovine virus diarrhoea-mucosal disease virus. Indirect immunofluorescence is used to detect infected MDBK cells in the wells of Terasaki plates. The virus titre is derived from the number of uninfected wells, using the Poisson distribution. The assay is simple, fast and economical. Titres of cytopathic virus determined by the microtitration assay and standard plaque assay are equivalent.

Prevalence of antibodies to bovine virus diarrhoea-mucosal disease virus in Tanzanian cattle.

A serological survey to determine the prevalence of antibodies to bovine virus diarrhoea-mucosal disease (BVD-MD) virus was conducted on 419 bovine serum samples originating from 18 of 20 regions (except Mwanza and Shinyanga) of the Tanzania mainland. The sera were a small proportion of samples collected for the appraisal of immune response to rinderpest vaccination. The survey indicated that the virus is prevalent in cattle populations and approximately 12% of sera tested contained demonstrable neutralising antibodies against BVD-MD virus.

牛ウイルス性下痢・粘膜病ウイルスの胎内感染に起因する先天性異常を有する新生子牛2例の疫学および病理学的観察

牛ウイルス性下痢・粘膜病ウイルスの胎内感染に起因する先天性異常を有する新生子牛2例の疫学および病理学的観察