An epidemic of parapoxvirus infection among cattle: isolation and antibody survey.

A disease characterized by papules, nodules, vesicles and, rarely, pustules and ulcers on teats was seen among cattle on a farm in Chiba Prefecture, Japan. A virus was isolated by inoculation of fetal bovine lung cell cultures from a vesicle on a teat of an infected cow. The virus was subsequently passaged in fetal bovine lung and muscle cells in which it produced complete cytopathic changes. The virus was identified by physicochemical examinations and electromicroscopic observation as a parapoxvirus. A seroepidemiological survey was performed on antibody to the isolated virus by the agar gel immunodiffusion test. The isolated virus formed a precipitation line which cross reacted with other parapoxviruses isolated previously in Japan. The positive rate was more than 50% among cattle in the Kanto district. The positive rate increased with age. It was suggested that parapoxvirus infection might have already been prevalent among cattle in Japan.     

TUBERCULIN SENSITIVITY OF CATTLE INOCULATED WITH ATYPICAL MYCOBACTERIA ISOLATED FROM CATTLE, FERAL PIGS AND TROUGH WATER

Each of 12 cattle was inoculated either subcutaneously and intradermally or into a mesenteric lymph node with 1 of 8 species of live atypical mycobacteria isolated from cattle, cattle trough water and feral pigs. Seventy-eight days after inoculation the cattle were tuberculin tested with bovine PPD, avian PPD and homologous heat-concentrated syntheic medium tuberculins. They were killed 85 days after inoculation. Organisms were cultured from caseous granu-lomas at all sites in cattle inoculated with M. avium serotype 2. M. simiae was recovered from a granuloma at the subcutaneous site. Acid-fast bacilli were isolated from the mesenteric lymph node inoculated with trough water organisms. At 72 h, all the cattle had produced skin reactions of 4 mm or more to the homologous tuberculins and all except 1 produced a similar response to avian PPD. Only isolates of bovine origin sensitised cattle to bovine PPD to this degree, and these reactions were less than the corresponding response to avian PPD.     

Production of cattle immunotolerant to bovine viral diarrhea virus.

Inoculation of bovine virus diarrhea virus into 58 to 125 day old fetuses of bovine virus diarrhea virus seropositive pregnant cows, or inoculation of bovine virus diarrhea virus into seronegative cows 42 to 114 days pregnant, may produce clinically normal calves which are persistently infected with the specific isolate of bovine virus diarrhea virus yet seronegative to the homologous and heterologous isolates. Reinoculation of these persistently infected cattle with their homologous isolate produced no neutralizing antibody response to bovine virus diarrhea virus. These persistently infected cattle were immunocompetent as they developed neutralizing serotiters to infectious bovine rhinotracheitis, parainfluenza-3 viruses and agglutinating serotiters to Pasteurella hemolytica .     

Epizootiologic Studies of Shipping Fever of Cattle: I. The Microbial Agents Isolated

Nineteen strains of Pasteurella spp., but no viruses cytopathogenic for bovine embryonic kidney cells were isolated from pneumonic lesions present in “normal” veal calves at slaughter.

In studies on two herds of native cattle and six lots of western feeder calves, Pasteurella spp. were isolated from nasal swabs from healthy cattle and those with shipping fever. Viruses of the psittacosis-lymphogranuloma group were isolated from nasal swabs from animals in five groups. Viruses provisionally identified as bovine enteroviruses were isolated from nasal swabs of calves in two lots.

There was serologic evidence of a temporal association of myxovirus para-influenza 3 (PI3) with shipping fever in three lots of calves. From two of these three lots, strains of PI3 were isolated from ten animals, four of which had clinical shipping fever at the time of virus isolation.

     

Response of cattle persistently infected with bovine virus diarrhoea virus to bovine leukosis virus

Six cattle persistently infected with bovine virus diarrhoea virus (BVDV) and seronegative, and two control, virus negative seropositive cattle were inoculated with lymphocytes infected with bovine leukosis virus (BLV). The two controls produced a normal immune response to BLV, developing antibodies at four and five weeks after inoculation. Two of the six cattle persistently infected with BVDV developed a strong antibody response by six weeks after inoculation with BLV. Four developed a depressed response to BLV, characterised in three by a 'hooking' reaction in the immunodiffusion test which persisted in successive bleedings but was interspersed occasionally by a weak positive reaction. In one of these animals, a series of 'hooking' reactions was followed by a number of negative results. The fourth animal remained serologically negative until 16 weeks after inoculation when a 'hooking' reaction was observed followed by a series of negative results. BLV was isolated from all the cattle persistently infected with BVDV at 42 or 58 weeks after inoculation regardless of whether the serum samples gave negative, 'hooking', weak positive or positive reactions in the immunodiffusion test. BLV was consistently isolated from the nasal secretions of a steer which was BVDV negative but seropositive. The possibility of decreased immune responsiveness to BLV in animals persistently infected with BVDV should be considered when formulating regulations governing the testing of animals for freedom from BLV.     

Variations of response of cattle to experimentally induced viral papillomatosis.

The common bovine papilloma virus type 1 has been widely used to stimulate basic research on papilloma viruses involved in some cancers of mankind. The usually benign neoplasms of cattle caused by bovine papilloma viruses are frequent clinical problems for veterinarians. Approximately 240 experimentally induced cutaneous fibropapillomas on 8 susceptible calves had a uniform appearance of initial growth. Their size and duration ranged from about 2 months to nearly 3 years but were similar for the multiple papillomas of each calf. Sequential biopsies were done to examine the histologic changes and existence of viral antigen. Veterinarians in practice may encounter the common fibropapillomas caused by bovine papilloma virus 1 and 2 as well as papillomas with no fibromatous element. These types may develop on teats of cows in some herds. Interdigital papillomas cause a problem in some dairy herds and a virus suspected but not yet found. Prophylactic vaccination with a formalin-killed vaccine will protect against infection with bovine papilloma virus 1 and 2.     

An immunofluorescence diagnostic test for feline viral rhinotracheitis.

Hyperimmune serum against feline viral rhinotracheitis was produced in a goat and conjugated with a fluorescent dye. Cell cultures infected with rhinotracheitis virus had positive immunofluorescence. Cell cultures infected with other feline viruses and herpesviruses of other species did not fluoresce. In cats experimentally infected with rhinotracheitis virus, the virus was isolated from nasal and conjunctival swabs 1 to 9 days after inoculation. Nasal smears stained with the conjugated antiserum fluoresced 1 to 9 days after inoculation when clinical disease was most apparent. Conjunctival smears had positive immunofluorescence 1 to 6 days, but not 9 days, after inoculation. On postinoculation day 23, rhinotracheitis virus was not isolated from nasal or conjunctival swabs and nasal and conjunctival smears did not fluoresce. Rhinotracheitis virus or feline calicivirus was isolated from naturally infected cats with upper respiratory tract disease. Nasal and conjunctival smears from rhinotracheitis virus-infected cats had positive immunofluorescence in all cast showing clinical illness. Smears from 1 clinically normal cat from which rhinotracheitis virus was isolated did not fluoresce. Nasal and conjunctival smears from calicivirus-infected cats did not fluoresce.     

PATHOGENICITY FOR CATTLE OF ATYPICAL MYCOBACTERIA ISOLATED FROM FERAL PIGS AND CATTLE AND THE CORRELATION OF LESIONS WITH TUBERCULIN SENSITIVITY

Two experiments involving the inoculation of cattle with atypical mycobacteria are described. In the first experiment groups of 5 cattle were inoculated either subcutaneously or into a mesenteric lymph node with a strain of M. scrofulaceum or M. intracellulare. Four weeks and 10 weeks after inoculation the cattle were tuberculin tested with bovine PPD, avian PPD and homologous PPDs. The pathological changes observed were similar within each group of cattle inoculated with the same strain of mycobacteria. A significant interaction was demonstrated between the strain and the route of inoculation. In the second experiment 17 cattle were similarly inoculated by either of the two routes with 1 of 6 strains of M. intracellulare, a strain of M. scrofulaceum or a strain of Runyon Group IV, all of which had been isolated from feral pigs, or a strain of M. intracellulare of bovine origin. Tuberculin tests were carried out after 4 weeks and 10 weeks. Only the isolate from a bovine lymph node produced a significant level of sensitivity to bovine PPD. Cultural isolation of the mycobacteria from autopsy material was not correlated with the presence of macroscopic lesions nor with sensitivity to bovine PPD. The response to bovine PPD of cattle infected with these atypical mycobacteria decreased between 48 h and 96 h after injection of the tuberculins. As the maximum difference in the response to bovine and avian tuberculins occurs at 72 h a comparative tuberculin test should be read at this time to eliminate non-specific reactors.     

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). All 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.     

Isolation and preliminary characterisation of some bovine enteric viruses

Fifty-eight faeces samples from calves and yearling cattle with diarrhoea were subject to a virus cultural study in monkey kidney cells and bovine embryonic kidney and lung cells. The properties of the 6 viruses isolated indicated that 5 were bovine enteroviruses belonging to 2 biologically different groups, and the remaining virus was probably a rotavirus (reo-like virus).     

Frequency of persistent bovine viral diarrhea virus infection in selected cattle herds

Sera and blood buffy coat samples were obtained from 3,157 cattle in 66 selected herds. Antibodies to bovine viral diarrhea (BVD) virus were detected in 89% of the serum samples by immunoprecipitation or virus-neutralization tests. Cytopathic or noncytopathic BVD viruses were isolated from blood buffy coat samples from 60 cattle in 6 herds. A second blood buffy coat sample was obtained from 54 of the 60 cattle 2 months after the initial sampling, and BVD virus was isolated again from each cow. The 54 cattle were considered persistently infected with BVD virus. The frequency of persistent infection was 1.7%.     

IBARAKI DISEASE AND ITS RELATIONSHIP TO BLUETONGUE

Ibaraki disease, an epizootic disease of cattle in Japan resembling bluetongue, is characterized by fever and lesions affecting the mucous membranes, the skin, the musculature and vascular system. Degeneration of striated muscular tissue is observed in the oesophagus, larynx, pharynx, tongue and the skeletal muscles. Oedema and haemorrhage are marked in the mouth, lips, abomasum, around the coronets, etc., and are occasionally followed by degeneration of the epithelium leading to erosions or ulcerations. Severe lesions affecting the oesophageal and laryngopharyngeal musculature cause difficulty in swallowing which in turn produces dehydration and emaciation, and occasionally the aspiration pneumonia, which constitute the major causes of death of affected animals. These clinical and pathological findings indicate the similarity of the disease to bluetongue in sheep and cattle. Ibaraki disease was first recognised in Japan in 1959 and 1960. Seasonally its occurrence is limited to late summer and autumn, and geographically to the central and western parts of Japan, roughly south of 37 degrees north latitude. It is absent from the higher altitudes. The seasonal and geographical incidence suggests the possibility of an arthropod vector; but direct evidence for such a vector is still lacking. Serological data suggest the presence of Ibaraki virus on Bali Island in Indonesia and in Taiwan. The disease can be transmitted serially in calves by the intravenous inoculation of blood obtained at the height of a febrile reaction. Ibaraki virus can be isolated in bovine cell cultures from both natural and experimentally produced cases of the disease. The virus multiplies and induces cytopathic effects in primary cultures of bovine, sheep and hamster lung origin, and L cells; but it does not grow in primary cultures of horse and swine kidney nor in HeLa cell cultures. The virus is readily passaged serially in 4 to 5-day-old eggs by yolk-sac inoculation and incubation at 33.5 degrees C. It multiplies in the brains of mice of any age after incracerebral inoculation but younger mice give a better viral growth and develop encephalitis. No evidence has been obtained that rabbits and guinea pigs are susceptible to Ibaraki virus...     

A paravaccinia virus isolated from cattle.

Isolation of viruses from calves with acute respiratory tract disease were attempted on bovine embryonic lung cell cultures. An isolate obtained from one calf with oral lesions and respiratory disease, designated 44-M-E482, was characterized as a paravaccinia virus on the basis of biological and physical properties. The calf from which the paravaccinia virus 44-M-E482 was isolated did not possess serum neutralizing antibody in its convalescent sera; neither did experimentally inoculated calves possess serum neutralizing antibody to the isolate. However, a low titer of serum neutralizing antibody was produced in one calf after several intravenous injections of the virus. Inoculation of calves with 44-M-E482 into the oral mucosa, skin, nasal cavity and pharynx did not cause any noticeable illness or lesions. The relation of 44-M-E482 to the viruses which cause bovine papular stomatitis and pseudocowpox is discussed.     

In vitro interferon production by bovine tissues: induction with infectious bovine rhinotracheitis virus.

The interferon-inducing ability of infectious bovine rhinotracheitis (IBR) virus was determined in tissue cultures of bovine origin inoculated with untreated and ultraviolet (UV) irradiated IBR viruses. Interferon was assayed by the plaque-reduction method in bovine fetal kidney (BFK) cell cultures, using vesicular stomatitis virus as challenge virus. Highest interferon concentrations were produced by cultures of bovine fetal (BF) spleen cells and aveolar macrophage cultures derived from adult cattle. Moderate interferon concentrations were produced by peripheral blood leukocyte (PBL) suspension cultures from adult cattle with serum-neutralizing antibodies against IBR virus. Cultures of PBL from 1 cow without detectable serum-neutralizing antibodies against IBR virus did not produce detectable interferon in response to IBR virus. Cultures of PBL from cattle with or without detectable serum-neutralizing antibodies against IBR virus produced interferon when stimulated with phytohemagglutinin (PHA). Low levles of viral inhibitors were detected infrequently in monolayer cultures of BFK and BF nasal mucosa inoculated with UV-irradiated IBR virus and in BF tracheal organ cultures inoculated with untreated IBR virus. Interferon was not detected in fluids collected from IBR virus-exposed monolayer cultures of primary and secondary BF lung, secondary BF tracheal mucosa, secondary BF liver, secondary BF adrenal, and PBL in the 4th and 7th passages. The antiviral inhibitors from BF spleen, bovine alveolar macrophage, and PBL cultures induced with IBR virus, as well as inhibitors from PBL cultures induced with PHA, had the usual properties of interferon.     

Virological and serological studies on the role of PI-3 virus, BRSV, BVDV and BHV-1 on respiratory infections of cattle. I. The detection of etiological agents by direct immunofluorescence technique

Nasal cells extracted from nasal swabs obtained from 95 cattle with signs of respiratory disease, out of eleven different herds, were tested for BHV-1, PI-3 virus, BRSV and BVDV using direct immunofluorescence technique. Viral antigen positive samples were detected in seven out of eleven herds examined. Of the 95 individual diseased cattle, 19 were found positive for at least one viral antigen. It was found that especially BHV-1 and PI-3 virus are important causative agents in cattle respiratory disease, both or in combination with other pathogenic agents. Multiple infection in virologically positive herds were observed in six (9.8%) of 61 animals tested. The findings reveal that single or multiple infections of selected viruses may be present in an important range in cattle and that direct immunofluorescence technique as a rapid method, based on the detection of viral antigen in nasal swab samples, is useful to establish the viral aetiology of acute bovine respiratory disease caused by these viruses, particularly in the diagnosis of mixed viral infections.     

Prevalence of antibodies to infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial, and bovine viral diarrhea viruses in cattle in Saskatchewan and Alberta

A total of 1745 healthy cattle from 295 farms in Saskatchewan and Alberta was tested by ELISA for antibodies to four viruses. Antibodies to infectious bovine rhinotracheitis (IBR) virus were found in 37.8% of sera (59.5% of properties), to parainfluenza 3 (PI3) virus in 93.9% of sera (99.7% of properties), to bovine respiratory syncytial (BRS) virus in 78.5% of sera (86.6% of properties), and to bovine viral diarrhea (BVD) virus in 40.6% of sera (66.7% of properties)

The prevalence of PI3 viral antibodies among Saskatchewan cattle was not affected by district of origin, breed, sex, age, or vaccination practices, though BRS viral antibodies appeared less frequent in young, male, and unvaccinated animals. Antibodies to IBR and BVD viruses were less prevalent in the Prince Albert/Tisdale districts and in young, male, and unvaccinated animals, but were more common in Holstein cattle. Antibodies to IBR virus appeared less frequent in Herefords. Antibodies were more prevalent in cattle which had been vaccinated against IBR, BRS, and BVD virus infections.

The relatively small number of cattle sampled from Alberta had a similar prevalence of antibodies to PI3 and BRS viruses to that seen in cattle in Saskatchewan, though IBR and BVD prevalence rates were lower.

     

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.     

The association between serological titers in infectious bovine rhinotracheitis virus, bovine virus diarrhea virus, parainfluenza-3 virus, respiratory syncytial virus and treatment for respiratory disease in Ontario feedlot calves.

A seroepidemiological study of the association between antibody titers to infectious bovine rhinotracheitis, parainfluenza-3, bovine virus diarrhea and bovine respiratory syncytial viruses, and treatment for bovine respiratory disease was conducted. A total of 322 calves from five different groups were bled on arrival, then one month later all cases (cattle treated for bovine respiratory disease) were rebled together with an equal number of controls (cattle not treated for any disease). Titers to these viruses varied significantly from group to group. Based on seroconversion, infectious bovine rhinotracheitis virus was active in 4.4%, bovine virus diarrhea virus in 24%, parainfluenza-3 virus in 69.5% and bovine respiratory syncytial virus in 71.3% of the cattle. Cattle with low titers to infectious bovine rhinotracheitis and/or bovine respiratory syncytial viruses on arrival, were at increased risk of subsequent treatment for bovine respiratory disease. Treated cattle also had significantly greater increases to parainfluenza-3 and/or bovine virus diarrhea viruses than control calves. Treatment rates varied considerably from group to group and were not strongly correlated with weight gain in the postarrival period.     

Infection of sheep and goats with bovid herpesvirus 2

Sheep and goats were shown to be susceptible to experimental infection with bovid herpesvirus 2 (BHV2), administered by either the intradermal or intravenous route. Lesions developing in sheep following intradermal inoculation of virus were similar to those in cattle inoculated intradermally, whereas the lesions in goats resolved without ulceration or scabbing. Disseminated circumscribed skin lesions developed in sheep and goats given BHV2 by the intravenous route. These lesions resolved in four to eight days without significant effect on the skin. BHV2 was isolated from skin lesions of sheep, goats and cattle that were infected intravenously, from sheep and cattle infected intradermally and from the leucocytes of the three species following intravenous inoculation of virus. Latent infection of sheep and goats was demonstrated following corticosteroid treatment 60 days after infection.     

Arboviruses recovered from sentinel cattle using several virus isolation methods

A group of 20 sentinel steers was bled weekly for 5 months in 1986 and the blood samples were examined for arboviruses by inoculation firstly into embryonated chicken eggs (ECE), baby mice, Aedes albopictus cells and BHK21 monolayers. A second group of cattle was similarly examined for virus in 1987, except that baby mice were not used. Viruses were recovered from 26% of the 878 weekly bleeds. The viruses identified consisted of 14 types belonging to the bluetongue, epizootic haemorrhagic disease (EHD), Palyam and Simbu groups with a single isolation of bovine ephemeral fever virus. The ECE system was found to be the best for isolating bluetongue and Simbu viruses, though the eggs were not usually killed by the inoculum. The ECE and A. albopictus systems were equally sensitive for recovering EHD viruses, while Palyam group viruses were most efficiently isolated in BHK21 monolayers.