Immunofluorescence in the serological diagnosis of parainfluenza type 3 and respiratory syncytial virus infection in calves

The fluorescent antibody (FA) test is compared with the haemagglutination inhibition (HI) test for parainfluenza virus type 3 (PI-3) and virus neutralisation (VN) test for respiratory syncytial (RS) virus for detection and titration of virus-specific antibodies. In experimentally inoculated calves PI-3 and RS virus FA tests detected seroconversion at the same time as HI and VN tests, however, in serially diluted sera, the FA test was positive to higher dilution. In studies with paired samples from calves from four farms with respiratory problems, the FA test gave similar results to PI-3 HI and RS virus VN tests. Large increases in antibody titre to RS virus detected by FA and VN tests indicated this was the problem on two of the farms. Individual animals showed large rises to PI-3 by FA and HI test on three farms. It is concluded that the FA test provides a rapid and sensitive alternative to the more conventional serological tests for respiratory viruses.     

Observations on outbreaks of respiratory disease in calves associated with parainfluenza type 3 virus and respiratory syncytial virus infection.

In four outbreaks of indoor calf pneumonia, dyspnoea was a prominent clinical finding. At necropsy it was associated with pneumonia involving the cranial lobes of the lung and severe pulmonary emphysema. Histological examination of lung tissue revealed bronchiolitis and alveolitis with alveolar epithelial cell hyperplasia and multinucleate syncytium formation. Intraalveolar haemorrhage, intra-alveolar oedema and hyaline membrane formation were also noted. In all cases parainfluenza type 3 (PI3) virus was isolated from the lungs. In each of the four outbreaks there was evidence of PI3 virus and respiratory syncitial virus (RSV) infection.     

Serological titers to bovine herpesvirus 1, bovine viral diarrhea virus, parainfluenza 3 virus, bovine respiratory syncytial virus and Pasteurella haemolytica in feedlot calves with respiratory disease: associations with bacteriological and pulmonary cytological variables.

Acute and convalescent serum samples were taken from 59 calves with signs of respiratory disease (cases) and 60 clinically normal animals (controls) during their first month in the feedlot. Sera were analyzed for antibodies to bovine parainfluenza 3 (PI3) virus by hemagglutination inhibition, to bovine viral diarrhea (BVD) virus, bovine respiratory syncytial (BRS) virus and bovine herpesvirus 1 (BHV1) by virus neutralization, and to Pasteurella haemolytica by indirect agglutination (PhIA) and cytotoxin neutralization (PhCN) tests. There was minimal evidence of serological activity to BHV1. Serological activity to the other agents occurred commonly and the prevalence of acute titers and their mean values was similar in case and control groups. Mean convalescent PI3 and P. haemolytica (PhIA) titers were higher in controls than cases (p < 0.01) but, otherwise, convalescent titers did not differ between groups. The incidence of seroconversion was similar in both groups for all agents except for PI3 virus which was more frequent in controls than cases (p < 0.0001). There was a positive association between PhIA and CN seroconversion and isolation of P. haemolytica from bronchoalveolar lavage (BAL) fluid (p < 0.1). The measure of agreement (kappa) between seroconversion with the P. haemolytica PhIA and PhCN tests was 0.51. Bacteriological and cytological evaluations of the respiratory tract were made using BAL. No associations were evident between serological titers and pulmonary cytology. A multivariate logistic analysis was used to evaluate associations between disease status and serological, bacteriological and cytological data. Cases were positively associated with the presence of neutrophils and Pasteurella multocida in BAL fluid and negatively associated with PI3 virus and PhIA seroconversion.     

Flunixin meglumine in calves with natural bovine respiratory syncytial virus infection

Twenty-three calves (three to eight months of age) with serological evidence of bovine respiratory syncytial virus infection were used in this study. The calves originated from four herds with respiratory tract disease. In a double blind trial the calves were injected intravenously with either flunixin meglumine (2 mg/kg body weight) or with a placebo. The effect on the course of disease was measured using the PO2 in capillary blood samples from the ears of the calves and by the effect on body temperature and respiratory rate. Mean body temperature fell significantly in the flunixin meglumine treated group. Statistically significant differences were not found between the treated and control group during the seven-day examination period.     

Detection of antibodies and risk factors for infection with bovine respiratory syncytial virus and parainfluenza virus-3 in beef cattle of Yucatan, Mexico

We collected blood samples from 756 > or =2-year-old cattle in 54 herds in Yucatan, Mexico, and used all of those to determine the antibody seroprevalences (in an indirect enzyme-linked inmunosorbance assay) to bovine respiratory syncytial virus (BRSV) and risk factors for animal-level seropositivity. We used 728 of the same samples (from 52 of the same herds) to do the same for parainfluenza virus-3 (PIV3). Cattle were selected by two-stage cluster sampling. Herd-level and animal-level risk factors were obtained through a personal interview. We analyzed the data by using a random-effects multivariable logistic regression model for clustered observations. All herds had at least 3 (BRSV) or 5 (PIV3) seropositive animals. The animal-level true seroprevalences were: 90.8% (86.5, 95.2%) and 85.6% (80.9, 90.4%) for BRSV and PIV3, respectively. Animals in large herds and old animals had the highest odds of being seropositives to BRSV, and those risk factors plus animals born on the farm for PIV3 infection.     

Protection against respiratory disease in calves induced by vaccines containing respiratory syncytial virus, parainfluenza type 3 virus, Mycoplasma bovis and M dispar

A field trial to assess the ability of two vaccines to protect calves against respiratory disease was carried out on a large beef rearing unit in southern England over the two winters of 1983 to 1984 and 1984 to 1985. A quadrivalent vaccine containing the killed antigens of respiratory syncytial virus, parainfluenza virus type 3, Mycoplasma bovis and M dispar or a vaccine containing only the respiratory syncytial virus component were inoculated into 246 and 245 calves, respectively; 245 calves remained as unvaccinated controls. The calves were reared in seven batches and outbreaks of disease occurred in five; significant protection was achieved in the four batches in which disease was associated with respiratory syncytial virus and M bovis infection, together or independently. The death rate from pneumonia was 9 per cent in the control group, 2 per cent in the calves inoculated with the quadrivalent vaccine (P less than 0.001), a protection rate of 77 per cent, and 3 per cent in the calves inoculated with the respiratory syncytial virus vaccine (P less than 0.01), a protection rate of 68 per cent. The proportion of calves receiving treatment for respiratory disease was 38 per cent in the control group, 25 per cent in the calves inoculated with the quadrivalent vaccine (P less than 0.001) and 27 per cent in the calves inoculated with the respiratory syncytial virus vaccine (P less than 0.01). The results show that protection against respiratory disease can be achieved by parenteral vaccination of calves with the appropriate inactivated microorganisms.     

Experimental bovine respiratory syncytial virus infection in conventional calves: ultrastructural respiratory lesions

The morphogenesis and repair of airway and alveolar injury induced by bovine respiratory syncytial virus (BRSV) was studied ultrastructurally in conventional calves to characterize pulmonary cell types susceptible to viral infection and cytopathologic changes associated with infection. Viral nucleocapsids and budding virions were present in tracheal and bronchial ciliated and nonciliated epithelial cells and mucous cells 3, 5, and 7 days after inoculation and in bronchiolar ciliated and nonciliated epithelial cells 5 days after inoculation. Mild interstitial pneumonia was observed 5 days after inoculation and was characterized by swelling of type 1 and type 2 alveolar epithelial cells, interstitial edema, and infiltration by lymphocytes and macrophages. Viral assembly and release in tracheal and bronchial epithelial cells was associated with loss of cilia from ciliated cells, formation of syncytial epithelial cells, swelling of mitochondria and endoplasmic reticulum, and cell necrosis. Neutrophils, lymphocytes, and macrophages were present in close association with the viral-infected and damaged epithelial cells. There was intercurrent hyperplasia of basal epithelial cells that, in association with other epithelial lesions, resulted in the loss of normal ciliated epithelium in these airways 5 and 7 days after inoculation. Regeneration of airway epithelium was largely completed by 10 days after inoculation, except in 1 of 4 calves that had failure of epithelial repair and that developed secondary bacterial pneumonia. Pulmonary ultrastructure in BRSV-inoculated calves 30 days after inoculation was indistinguishable from that in controls. The results demonstrated that BRSV can induce reversible alterations in airway epithelium, which may cause depression of mucociliary clearance and thereby enhance susceptibility to bacterial infection.     

Efficacy of an intranasal modified live bovine respiratory syncytial virus and temperature-sensitive parainfluenza type 3 virus vaccine in 3-week-old calves experimentally challenged with PI3V

Two experimental parainfluenza type 3 virus (PI3V) challenge studies were undertaken to evaluate the efficacy of a single intranasal dose of an attenuated live vaccine containing modified live bovine respiratory syncytial virus (BRSV) and temperature-sensitive PI3V in 3-week-old calves. In the first study, vaccine efficacy was evaluated in colostrum deprived calves. Nasal shedding of PI3V was highly significantly reduced in vaccinated calves challenged 10 days or 21 days after vaccination. In the second study, vaccine efficacy was assessed in calves with maternal antibodies against PI3V by challenge 66 days post-vaccination. Vaccination also significantly reduced PI3V excretion after challenge in this study. In both studies, clinical signs after challenge were very mild and were not different between vaccinated and control calves.     

Clenbuterol hydrochloride in calves with a natural bovine respiratory syncytial virus infection

The effect of clenbuterol hydrochloride on the course of disease in calves with a natural bovine respiratory syncytial virus infection was examined. Six calves (three to nine months of age) originating from four herds with respiratory tract disease and serological evidence of a bovine respiratory syncytial virus infection were used in this study. The calves were injected intravenously with clenbuterol hydrochloride. The effect of clenbuterol on the course of disease was measured using the PO2 in blood taken from an indwelling canula inserted in the caudal auricular artery and by clinical signs. Clenbuterol did not improve clinical signs. After clenbuterol administration arterial PO2 values decreased significantly in five out of six patients. Six to eight hours after medication the mean arterial PO2 values were higher than initial values. The moderate positive effect of clenbuterol after six to eight hours may be caused by enhancing ciliary activity and by the secretolytic activity of clenbuterol.     

Clinical signs following experimental lungworm infection and natural bovine respiratory syncytial virus infection in calves

Similar clinical signs have been reported in calves infected either by Dictyocaulus viviparus or bovine respiratory syncytial virus. Three experiments were carried out to establish the clinical picture and the course of the disease in animals with these infections. The clinical signs of calves infected with lungworm included coughing, nasal discharge, tachypnoea, abdominal breathing and pyrexia, and auscultation of their lungs revealed increased bronchial sounds. Similar signs were also observed after infection with bovine respiratory syncytial virus, but the signs were more acute and resolved more rapidly than in animals infected with lungworm larvae. Calves infected with lungworm had more serious clinical signs after infection with bovine respiratory syncytial virus than calves, which were not infected with lungworm.     

Mismatching of ventilation and perfusion in calves with natural bovine respiratory syncytial virus infection

The cause of arterial hypoxia during natural infection with bovine respiratory syncytial virus was studied in seven calves (three to nine months of age) originating from five herds with respiratory tract disease and serological evidence of infection with the virus. Blood gas values were measured during ambient air breathing and during 100 per cent oxygen breathing. The percentages of contribution to the arterial hypoxia from alveolar hypoventilation, mismatching of ventilation and perfusion, and right-to-left shunting were calculated from the measured parameters. Calculated percentages of total venous admixture varied from 14 per cent of cardiac output in relatively mild cases to 48 per cent in the worst affected animal. This venous admixture had been caused mainly by right-to-left shunting of blood, while mismatching of ventilation and perfusion became important in the more severely affected animals. Alveolar hypoventilation was only important in the worst affected animal.     

Experimental infection of calves with bovine respiratory syncytial virus (Quebec strain).

An experiment was designed to evaluate the clinical, haematological, viral and serological aspects of bovine respiratory syncytial virus infection in calves. Eleven calves were inoculated intranasally with bovine respiratory syncytial virus (Quebec strain) in aerosol. Clinical, haemotological and serological responses of the calves and virus shedding were monitored. The experimentally infected animals manifested moderate to severe signs of respiratory disease. The parameters used to evaluate the severity of the disease included ocular discharge, conjunctivitis, lung sounds, nasal discharge, pyrexia and leukopenia. The animals were scored accordingly (scale infected 70.8-148.5, control 22-29.3). Highest disease scores were observed between day 6-9 after infection. Virological and serological assessment demonstrated that the observed clinical picture was due to bovine respiratory syncytial virus infection.     

Pulmonary lesions induced by 3-methylindole and bovine respiratory syncytial virus in calves

Our objectives were to describe the ultrastructural morphogenesis of pulmonary lesions induced by 3-methylindole in 30- to 45-day-old Holstein calves and to determine whether toxic exposure to 3-methylindole exacerbates pulmonary lesions induced by bovine respiratory syncytial virus. Administration of 3-methylindole (0.25 g/kg) to calves resulted in interstitial edema and ultrastructural swelling of type-I alveolar epithelial cells and nonciliated bronchiolar epithelial cells as early as 4 to 6 hours after intraruminal administration. More severe alveolar edema containing protein was associated with swelling of capillary endothelial cells at 2 days after administration. Proliferation of type-II alveolar epithelial cells was first observed at 2 days after 3-methylindole administration, and marked hyperplasia of type-II epithelial cells and nonciliated bronchiolar epithelial cells was evident by 4 days after administration. Pulmonary cytochrome P-450 monooxygenase concentrations decreased significantly (P less than 0.001) by 12 hours after administration and did not increase significantly again by 8 days after administration. Calves were inoculated with bovine respiratory syncytial virus 3 days after administration of 3-methylindole, and pulmonary lesions were assessed 5 days after viral inoculation. Viral replication was demonstrated by fluorescence microscopy for viral antigen or by transmission electron microscopy in ciliated and nonciliated airway epithelial cells. Viral antigen was identified infrequently in alveolar macrophages and in type-II alveolar epithelial cells. 3-Methylindole exposure in calves did not result in more widespread distribution of viral antigen in alveolar tissue of respiratory syncytial virus-inoculated calves or in significant enhancement of viral pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Replication of parainfluenza type-3 virus and bovine respiratory syncytial virus in isolated bovine type-II alveolar epithelial cells.

The objectives of our research were to determine whether bovine pulmonary type-II alveolar epithelial cells could be isolated from bovine lung and maintained in tissue culture and to determine whether isolated bovine type-II alveolar epithelial cells would support productive viral replication of bovine parainfluenza type-3 virus and bovine respiratory syncytial virus. Type-II alveolar epithelial cells were isolated from lungs of 4- to 7-day-old male Holstein calves by enzymatic dissociation of pulmonary tissue with trypsin and by separation of cells with the use of filtration and centrifugation on continuous Percoll gradients. Cells were further separated by panning on IgG-coated plastic plates and by lectin binding. Isolated type-II alveolar cells were maintained on basement membrane-coated tissue cultured plates. In culture, type-II cells formed alveolar structures and maintained other cytologic features of type-II cells, including osmiophilic lamellar inclusions. Cell cultures were inoculated with and supported productive replication of bovine parainfluenza type-3 virus and bovine respiratory syncytial virus. This was determined by recovery of infectious viruses from inoculated cell cultures and by identification of viral structures in type-II alveolar epithelial cells by transmission electron microscopy.     

Serological evidence of respiratory syncytial virus infection in lambs

Abstract

Extract

Madam;–The results of field trials of a live parainfluenza virus type3(PI₃)vaccine suggested that(PI₃)might not be the only virus involved in the initiation of outbreaks of pneumonia in lambs in New Zealand,(5 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])The outbreaks that were not associated with infection with(PI₃)could not be linked to infection with the other ovine respiratory viruses then known to be present in New Zealand (ovine adenovirus type 6 and the ovine variant of bovine adenovirus type 7)((1 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar]),(4 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar]),(5 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])suggesting that other unrecognised viruses might be involved. Respiratory syncytial virus (RSV) is a major cause of pneumonia in human infants and in cattle.(8 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])This virus has recently been isolated from a yearling ewe with mild rhinitis(6 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])and there is serological evidence of infection in adult sheep.(3 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar]),(6 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])However, there are no reports implicating this virus in outbreaks of pneumonia in lambs, although experimental infection of lambs with a bovine isolate of RSV resulted in reduced pulmonary bacterial clearance leading to secondary pneumonic pasteurellosis.(2 Adair, B.M., McFerran, J.B. and McKillop, E.R. 1982. A sixth species of ovine adenovirus isolated from lambs in New Zealand. Arch. Virol., 74: 269–269. [Crossref] , [Google Scholar])     

Detection of antibodies and risk factors for infection with bovine respiratory syncytial virus and parainfluenza virus 3 in dual-purpose farms in Colima, Mexico

A cross-sectional study was carried out, from November 2007 to March 2008, to estimate the prevalence of and to determine risk factors associated with bovine syncytial respiratory virus (BRSV) and parainfluenza 3 virus (PIV3) in dual-purpose herds in Colima, México. One hundred and seventy-six sera from 33 herds for PIV3 and 232 sera from 44 herds for BRSV were used. Sera were analyzed by indirect ELISA for the detection of antibodies against BRSV and PIV3 in cattle herds to determine the seroprevalence of respiratory diseases. The apparent and true prevalences for PIV3 were 60.8% and 54.4% and for BRSV 52.2% and 50.8%, respectively. The percentage of herds showing at least one positive animal was 78.7% for PIV3, and 93.2% for BRSV. Age (≤12, 13-48, and >48?months old) and respiratory signs (no, yes) showed significant association (P?相似文献