共查询到20条相似文献，搜索用时 46 毫秒
1.
Recurrent infection by infectious bovine rhinotracheitis (IBR) virus was induced in calves by dexamethasone (DM) treatment (given 5 days) at 5 months after primary infection. The virus appeared in nasal secretions of the calves on the 4th day after initiation of DM treatment and continued until the 9th day. The calves were killed on the 1st, 3rd, 4th, 5th, 6th, 7th, 8th, 10th, and 11th days after DM treatment was started for examination by histopathologic and immunofluorescent antibody techniques. The most significant neural change was trigeminal ganglionitis with neuronophagia, which was observed from the 3rd to the 11th day. Significantly, the extent of changes in the trigeminal ganglion and medulla oblongata corresponded to the amount of DM treatment administered. The IBR virus antigen was first observed in the trigeminal ganglion cells, and thereafter, it was detected in the Schwann cells, satellite cells, neuroglia cells, and nasal mucosa until the 10th day. These observations indicate that the IBR virus is capalbe of producing a persistent infection in the trigeminal ganglion and that trigeminal ganglionitis may be a characteristic lesion for inducing the reactivation of lagent IBR virus. 相似文献
2.
Recurrent infection in calves vaccinated with infectious bovine rhinotracheitis-(IBR) modified live virus was induced by dexamethasone (DM) treatment given 49 days after challenge exposure with virulent IBR virus. Nonchallenge-exposed IM and intranasally vaccinated calves did not excrete the virus after DM treatment; however, IM and intranasally vaccinated and subsequently challenge-exposed calves excreted the challenge-exposure virus into the nasal secretions 5 to 11 days and 6 to 10 days after the DM treatment, respectively. The calves were killed 15 to 18 days (experiment 1) and 14 days (experiment 2) and DM treatment was started and then were examined by histopathologic and fluorescent antibody techniques. All DM-treated calves that were inoculated with the vaccinal virus and challenge exposed with the virulent virus developed nonsuppurative trigeminal ganglionitis and encephalitis. On the contrary, the DM-treated nonchallenge-exposed vaccinated calves did not have lesions in the peripheral nervous system and CNS. Infectious bovine rhinotracheitis virus antigens were not observed in tissues of any of the calves examined (experiments 1 and 2) by fluorescent antibody techniques. These observations indicated that the modified live IBR virus neither produced lesions nor induced latent infection and that modified live IBR virus vaccination did not protect the calves against the establishment of a latent infection after their exposure to large doses of the virulent IBR virus. 相似文献
3.
G Castrucci F Frigeri V Cilli B Tesei A M Arush B Pedini S Ranucci L Rampichini 《American journal of veterinary research》1980,41(11):1890-1893
A study was carried out to determine whether bovid herpesvirus-2 (BHV-2) is able to induce a recurrent infection in experimentally infected calves. Twelve calves infected with the virus were treated with dexamethasone (DMS) beginning 69 days after the infection, ie, several weeks after the animals had recovered from the disease and were negative for BHV-2. The stress induced by DMS treatment failed to reactivate the clinical condition or to induce shedding of BHV-2. However, treatment with DMS reactivated a latent infectious bovine rhinotracheitis (IBR) virus infection in all calves previously inoculated with BHV-2, and also in 2 noninoculated controls. The reactivation of IBR virus occurred without any clinical evidence of the disease, but the virus was isolated from nasal and pharyngeal swabbings and from the organs. A proliferative ganglionitis of the trigeminal ganglion was also observed. Because of the interference by IBR virus, this study did not resolve the question as to whether BHV-2 can induce a recurrent infection. 相似文献
4.
A latent infection of bovine herpesvirus-5 (BHV-5) was established in 4 calves. These calves, plus 2 controls, were given dexamethasone (DM) to reactivate the latent virus. The 4 principal calves developed antibodies to BHV-5 by postinoculation day (PID) 21. Antibody titers increased until PID 42 before decreasing to low levels of PID 75. After the first DM treatment (started on PID 76), an anamnestic antibody response was demonstrated in the 4 principal calves. Calves, 2, 3, and 4 were euthanatized and necropsied at PID 121, and their antibody titers were again decreasing. The virus BHV-5 was not isolated from the tissues by conventional techniques of viral isolation but was isolated from the trigeminal ganglion and spinal cord of calf 3 by explantation techniques. The BHV-5 was isolated, using conventional viral isolation techniques, from a nasal swab sample of calf 1 on PID 91 (15 days after the first DM treatment) and from the thoracic lymph node 6 days after the start of a 2nd DM treatment. Seemingly, BHV-5 may be latently harbored in the nerve tissues or calves and this virus may be reactivated from the upper respiratory tract following subsequent DM treatment. 相似文献
5.
Six calves inoculated intranasally with a vaccinal strain of infectious bovine rhinotracheitis (IBR) virus and 6 control calves were given a placebo. All calves were subsequently challenge exposed (by aerosol) with rhinovirus--3 of the calves from each group at 2 days after they were inoculated with IBR virus or with placebo and the remaining calves at 6 days. Nasal excretion of viruses, interferon (IFN) concentrations in nasal secretions (NS), and neutralizing antibody in sera and NS were determined. All calves given the vaccinal IBR virus subsequently had IFN in their NS. Interferon was detected as early as 1 day, reached maximal titers at 2 to 4 days, and persisted in individual calves for 5 to 10 days after inoculation. Rhinovirus shedding was not detected from IBR virus-inoculated calves whose NS contained both rhinovirus antibody and IFN at the time of challenge exposure; such calves were protected at either 2 or 6 days after IBR virus inoculation. The outcome of rhinovirus challenge exposure of calves whose NS contained IFN, but not rhinovirus antibody, varied with the day of challenge exposure. Rhinovirus excretion was detected from 2 of these calves challenge exposed 2 days after IBR virus inoculation, but was not detected from a calf challenge exposed 6 days after inoculation. However, while IFN was present in NS from the former 2 calves, rhinovirus shedding was markedly reduced as compared with that from control calves without IFN or NS antibody at the time of challenge exposure. Consistent relationship was not observed between the rhinovirus neutralizing antibody titer of calves' sera and NS. The antibody titer of NS more closely correlated with protective immunity to rhinovirus infection than did the serum antibody titer. 相似文献
6.
Calves not vaccinated with infectious bovine rhinotracheitis virus (IBRV) became latently infected when challenge exposed and treated with dexamethasone (DM). Calves that shed IBRV after DM treatment were considered to be latently infected. Vaccination with a temperature-sensitive intranasal vaccine or with formalinized IBRV in Freund's complete adjuvant (IBRV-FCA) protected some, but not all, calves against latent infection--indicating a role for the immune response in preventing latent infection. That all latently infected calves were not detected after DM treatment was indicated by the fact that after a 2nd DM treatment of 3 calves treated 6 months previously and not found to shed virus, 1 of the calves was latently infected. Latently infected calves were inoculated with successive doses of IBRV-FCA and treated with DM. Nonvaccinated calves shed virus, whereas vaccinated calves similarly treated did not shed virus. Because both groups had a comparable cell-mediated immune response, as determined by blastogenic response to IBRV, but the vaccinated group had significantly higher virus-neutralizing antibody titers, a role for humoral antibody in preventing viral shedding was indicated. 相似文献
7.
G. Castrucci M. Ferrari V. Traldi E. Tartaglione 《Comparative immunology, microbiology and infectious diseases》1992,15(4):261-270
The objective of this study was to verify whether a mixed infection in calves with bovine viral diarrhea virus (BVDV) and other bovine viruses, such as bovid herpesvirus-4 (BHV-4), parainfluenza-3 (PI-3) and infectious bovine rhinotracheitis (IBR) virus, would influence the pathogenesis of the BVDV infection sufficiently to result in the typical form of mucosal disease being produced.
Accordingly, two experiments were undertaken. In one experiment calves were first infected with BVDV and subsequently with BHV-4 and IBR virus, respectively. The second experiment consisted in a simultaneous infection of calves with BVDV and PI-3 virus or BVDV and IBR virus.
From the first experiment it seems that BVDV infection can be reactivated in calves by BHV-4 and IBR virus. Evidence of this is that BVDV, at least the cytopathic (CP) strain, was recovered from calves following superinfection. Moreover, following such superinfection the calves showed signs which could most likely be ascribed to the pathogenetic activity of BVDV. Superinfection, especially by IBR virus, created a more severe clinical response in calves that were initially infected with CP BVDV, than in those previously given the non-cytopathic (NCP) biotype of the virus. Simultaneous infection with PI-3 virus did not seem to modify to any significant extent the pathogenesis of the experimentally induced BVDV infection whereas a severe clinical response was observed in calves when simultaneous infection was made with BVDV and IBR virus. 相似文献
8.
Infectious bovine rhinotracheitis (IBR) virus was isolated from the trigeminal ganglion of a feral pig after dexamethasone treatment. Three pigs inoculated intranasally with the IBR virus did not respond clinically or serologically. The virus was re-isolated from tonsillar swabs from two animals on Post-Infection Day (PID) 3. 相似文献
9.
Latent bovine herpesvirus-1 (BHV-1) infection was established in 6 calves and was demonstrated by reinduction of virus shedding after administration of corticosteroids. Latently infected calves failed to transmit BHV-1 during 4 weeks' contact with sentinel calves. Infected calves were killed and necropsied during latency or induced recrudescence. The BHV-1 DNA was demonstrated intranuclearly in trigeminal ganglion neurons by in situ hybridization. The BHV-1 antigen was demonstrated by immunofluorescence in trigeminal ganglion neurons during recrudescence. By electron microscopy, changes in the appearance of the Nissl bodies and a high frequency of nuclear bodies were observed in trigeminal ganglion neurons. 相似文献
10.
Four calves latently infected with infectious bovine rhinotracheitis virus (IBRV) were used to compare the ease of isolation of virus from neuronal ganglia and from mucosal surfaces. Two calves were slaughtered, and neuronal ganglia (cranial cervical, trigeminal, and 3rd and 4th sacral) were cocultivated on bovine fetal kidney cells. Virus was not isolated. Two calves given dexamethasone for 4 days were slaughtered on the 5th day. Virus was not isolated from cocultivated or macerated neuronal ganglia, but virus was isolated from nasal secretions taken from both calves on the day of slaughter. Eleven calves were inoculated with IBRV via different routes and were treated with dexamethasone 3 to 4 months after inoculation. virus was isolated from the nasal cavities, but not the vaginas of 6 heifers inoculated intranasally, and was isolated from the vaginas, but not the nasal cavities of 2 heifers inoculated intravaginally. Of 3 calves inoculated IV, virus was isolated from the nasal cavities of 3, from the oropharynxes of 2, and from the prepuce of 1. 相似文献
11.
A live Pasteurella haemolytica vaccine efficacy trial 总被引：3，自引：0，他引：3
C W Purdy C W Livingston G H Frank J M Cummins N A Cole R W Loan 《Journal of the American Veterinary Medical Association》1986,188(6):589-591
A live Pasteurella haemolytica serotype 1 vaccine was used in an efficacy trial conducted on 100 lightweight feeder calves purchased from a Florida ranch. Forty-one calves were inoculated with the vaccine intradermally in the neck. Fifty-nine calves served as nonvaccinated controls. Fourteen days later, the calves were shipped to an order buyer in eastern Tennessee, where the calves were mixed with 60 local calves in a community sale barn for 72 hours. After 3 additional days, the calves were shipped to a research feedlot in Bushland, Tex. They remained in the feedlot for 56 days, and the test was concluded 76 days after vaccination. The P haemolytica vaccine had no significant effect on performance, morbidity, or mortality. There was no significant difference between the vaccinated and nonvaccinated calves in the number of times Pasteurella was isolated. The calves became seropositive to bovine viral diarrhea virus, respiratory syncytial virus, and infectious bovine rhinotracheitis (IBR) virus during the 76-day experiment. All calves initially were seropositive to parainfluenza-3 virus. A virulent outbreak of IBR occurred 30 days after the calves arrived at the feedlot. Before the onset of IBR, the isolation of P haemolytica serotype 1 from nasal turbinates was rare (2 of 500 nasal swabs). After the IBR outbreak, P haemolytica serotype 1 was isolated from 40 of 92 calves. 相似文献
12.
The feeding of ethylenediamine dihydriodide (EDDI) at the dose levels of 50 and 500 mg/animal/day and urea at the dose level of 45 g/animal/day did not affect duration of clinical signs, body weight gain, magnitude or duration of fever, serum concentration of glutamic oxalacetic transaminase, packed cell volume, and differential white blood cell counts in feeder cattle experimentally infected with infectious bovine rhinotracheitis (IBR) virus. However, coughing and abundance of nasal discharge were significantly greater in calves fed EDDI before and during primary IBR virus infection. Those calves fed 500 mg of EDDI/day coughed more, had greater nasal discharge, and exhibited greater lacrimation than did those given the smaller dose. These 3 clinical signs were considered to reflect both the expectorant action of EDDI and the pathogenic effects of IBR virus. In all calves, including controls, the coughing, nasal discharge, and lacrimation were most prominent during the period of peak infection (7 to 14 days after the calves were given intranasal inoculation) of the IBR virus. Total serum iodine concentration became maximal (mean of 1,400 ng/ml) in 8 calves after they had been fed the larger dose of EDDI for 2 weeks. This value was maximal (about 300 ng/ml) in another 8 calves after 3 weeks' feeding of the smaller dose (50 mg/day). When EDDI exposure was maintained at the dose level of 50 mg/day for 5 weeks longer, mean serum iodine values remained at about 275 ng/ml, and those of control calves averaged 140 ng/ml. 相似文献
13.
R L Sweat 《Journal of the American Veterinary Medical Association》1983,182(8):809-811
Persistence of antibodies in calves vaccinated with 2 types of inactivated infectious bovine rhinotracheitis (IBR) virus and parainfluenza-3 (PI-3) virus vaccines were determined. Calves seronegative for IBR and PI-3 viruses were inoculated with 2 doses of inactivated IBR virus-PI-3 virus vaccines administered 2 weeks apart. Blood samples were obtained from the calves for serum at 2 weeks, 6 months, and 1 year after vaccination. The serums were tested by serum-neutralization tests. Antibody response to the vaccines persisted on a declining scale for 1 year. The anamnestic responses to the vaccines were determined by inoculating the same calves with a booster dose of vaccine 1 year after the original 2 doses were given. Blood samples were obtained from the calves for serum 2 weeks later. The serums were tested by serum-neutralization tests. The single booster dose of vaccine elicited an anamnestic response to both IBR and PI-3 viruses. 相似文献
14.
S van Drunen Littel-van den Hurk D Myers P A Doig B Karvonen M Habermehl L A Babiuk M Jelinski J Van Donkersgoed K Schlesinger C Rinehart 《Canadian journal of veterinary research》2001,65(2):81-88
Outbreaks of infectious bovine rhinotracheitis (IBR) have recently been observed in vaccinated feedlot calves in Alberta a few months post-arrival. To investigate the cause of these outbreaks, lung and tracheal tissues were collected from calves that died of IBR during a post-arrival outbreak of disease. Bovine herpesvirus-1 (BHV-1), the causative agent of IBR, was isolated from 6 out of 15 tissues. Of these 6 isolates, 5 failed to react with a monoclonal antibody specific for one of the epitopes on glycoprotein D, one of the most important antigens of BHV-1. The ability of one of these mutant BHV-1 isolates to cause disease in calves vaccinated with a modified-live IBR vaccine was assessed in an experimental challenge study. After one vaccination, the majority of the calves developed humoral and cellular immune responses. Secondary vaccination resulted in a substantially enhanced level of immunity in all animals. Three months after the second vaccination, calves were either challenged with one of the mutant isolates or with a conventional challenge strain of BHV-1. Regardless of the type of virus used for challenge, vaccinated calves experienced significantly (P < 0.05) less weight loss and temperature rises, had lower nasal scores, and shed less virus than non-vaccinated animals. The only statistically significant (P < 0.05) difference between the 2 challenge viruses was the amount of virus shed, which was higher in non-vaccinated calves challenged with the mutant virus than in those challenged with the conventional virus. These data show that calves vaccinated with a modified-live IBR vaccine are protected from challenge with either the mutant or the conventional virus. 相似文献
15.
OBJECTIVE: To measure associations between health and productivity in cow-calf beef herds and persistent infection with bovine viral diarrhea virus (BVDV), antibodies against BVDV, or antibodies against infectious bovine rhinotracheitis (IBR) virus in calves. ANIMALS: 1,782 calves from 61 beef herds. PROCEDURES: Calf serum samples were analyzed at weaning for antibodies against type 1 and type 2 BVDV and IBR virus. Skin biopsy specimens from 5,704 weaned calves were tested immunohistochemically to identify persistently infected (PI) calves. Herd production records and individual calf treatment and weaning weight records were collected. RESULTS: There was no association between the proportion of calves with antibodies against BVDV or IBR virus and herd prevalence of abortion, stillbirth, calf death, or nonpregnancy. Calf death risk was higher in herds in which a PI calf was detected, and PI calves were more likely to be treated and typically weighed substantially less than herdmates at weaning. Calves with high antibody titers suggesting exposure to BVDV typically weighed less than calves that had no evidence of exposure. CONCLUSIONS AND CLINICAL RELEVANCE: BVDV infection, as indicated by the presence of PI calves and serologic evidence of infection in weaned calves, appeared to have the most substantial effect on productivity because of higher calf death risk and treatment risk and lower calf weaning weight. 相似文献
16.
The course of infection and IBR virus reactivation was studied in three experimentally infected weaned calves and three cows from naturally invaded herds. The animals were infected intranasally, intratracheally, and by contact. After 20, 41, and 105 days from primary infection, both in calves and in cows, dexametazon was applied in a series of six to seven intramuscular injections. The presence of the virus was examined in the nasal, conjunctival, vaginal and/or preputial secretions and in blood on diploid cells of calf kidneys and by the immunofluorescence method. In all infected calves, the disease took place with clinical signs of rhinotracheitis, mostly within the period of nine days. The second and third day after a temperature rise, the virus titre in nasal secretion reached the values ranging from 10(5) to 10(6.5). A markedly lower titre was obtained in the conjunctival secretion 10(0.5) to 10(3.5). In blood, the virus was found to be present on the first and fifth day from infection. After dexametazon application the calves and cows eliminated the virus mainly with the nasal secretion whose titre highly rose to the value of 10(3.5) to 10(47). In the conjunctival secretion the virus was present only irregularly and its quantities were very small. The greatest quantities of the virus were found in the nasal secretion on the sixth to the eight day from dexametazon application. The virus was not found in vaginal and preputial secretions. The levels of neutralizing antibodies were not affected by dexametazon in the calves; in cows they rose significantly from the titres of 1:2--1:4 to the titres of 1:16--1:32. 相似文献
17.
Correlations between leukocyte counts and serum interferon titers were determined in calves given hydrocortisone (HC) and infectious bovine rhinotracheitis (IBR) virus. Calves were injected with either 1 mg or 3 mg of HC/kg of body weight every 8 hours for a total of 9 injections each. Control calves were given placebo injections. Viral inoculation was given IV 10 hours after the 1st dose of HC or placebo was given. By the time of viral inoculation, all calves injected with HC had developed neutrophilia, and the calves injected with 3 mg of HC also developed leukocytosis, lymphopenia, and eosinopenia; total leukocyte counts in calves injected with 1 mg of HC were increased, but not as much as in other HC-treated calves. Leukocyte counts in calves given placebo remained essentially unchanged before viral inoculation. At 1 day after IBR virus was inoculated, the number of circulating lymphocytes in HC-treated calves and control calves was decreased by more than 50%, on the average, of the counts taken before the HC injections or inoculation of virus. A significant negative correlation existed between the numbers of circulating lymphocytes and serum interferon titers at 1, 2, and 3 days after inoculation with IBR virus. The interferon response of calves undergoing lymphocyte suppression due to HC was not impaired, but was enhanced. 相似文献
18.
M R Irwin C A Holmberg H D Knight C A Hjerpe 《American journal of veterinary research》1976,37(2):223-226
In a study on the primary humoral response of calves vaccinated against infectious bovine rhinotracheitis (IBR) and simultaneously given levamisole, mild but consistent suppression of the group's geometric mean serum-neutralization titer to IBR virus occurred between 12 and 59 days later. The quantitative determination of circulating immunoglobulins (Ig) over the same period indicated a slight decrease in the IgG concentrations from an initial geometric mean concentration of 18.28 mg/ml before calves were vaccinated to 15.29 mg/ml after vaccination, and the control calves (vaccinated and given saline solution only) maintained their prevaccination IgG geometric mean concentration of 20.92 mg/ml. Difference was not observed in the circulating IgM values of the 2 groups. Levamisole had no apparent effect on the circulating Ig-bearing lymphocyte values when compared with control calves during the 24 hours of treatment. It was concluded that a single treatment of levamisole may mildly suppress the primary humoral response to IBR vaccination in calves, but it is unlikely that this would affect the animal's capability to recover from, or maintain resistance to, IBR infection. 相似文献
19.
G Castrucci V Cilli F Frigeri M Ferrari S Ranucci L Rampichini 《Comparative immunology, microbiology and infectious diseases》1983,6(3):193-199
Two experiments were carried out to determine whether Bovid herpsvirus (BHV) 2 is able to induce a recurrent infection in experimentally infected calves. In the first experiment the stress induced by dexamethasone (DMS) treatment failed to reactivate the clinical condition or to induce shedding of BHV2. However, treatment with DMS reactivated a latent BHV1 infection in all calves previously inoculated with BHV2 and also in two noninoculated controls. Probably, because of the interference by BHV1 the study failed to resolve the question as to whether BHV2 could induce a recurrent infection. Consequently, a second experiment was performed using calves devoid of antibody to BHV1 and, therefore, probably, free of virus. By this study it was demonstrated that BHV2 can remain as a latent infection in cattle, which, when immunosuppressed as with DMS, can be reactivated. A finding of considerable interest in this experiment was that in 1 calf a concurrent piroplasma infection was also, unexpectedly, discovered.Recrudescence of latent BHV1 infection was induced by DMS treatment of calves possessing antibody to the virus. The infection once reactivated, was readly transmitted by contact to three other calves devoid of antibody to BHV1. In the same experiment Parainfluenza-3 (PI-3) virus was unexpectedly isolated from all calves. It was speculated that all calves were latently infected with PI-3 virus with concurrent infection by BHV1 acting as a stress inducing PI-3 reactivation.These studies seem to indicate that mixed infections could have an important role in the mechanism involved in the establishment of latent infections and viral reactivation. 相似文献
20.
DNA of bovine herpesvirus type 1 in the trigeminal ganglia of latently infected calves 总被引：8，自引：0，他引：8
Twelve calves infected with bovine herpesvirus type 1 (BHV-1) were killed when in a latent state of infection. Latency was verified 30 days after virus inoculation of the calves by seroconversion, absence of virus shedding, and in 2 calves, by recrudescence of the infection after they were treated with dexamethasone. By in situ hybridization techniques and autoradiography, DNA of BHV-1 was detected in 13 of 23 trigeminal ganglia of latently infected calves. Viral DNA was restricted to the nucleus of nerve cells. Single neurons harboring BHV-1 DNA were observed in 4.9% of the sections (n = 325) of the trigeminal ganglia. The results obtained correspond to those known from herpes simplex virus infections in mice. The implications for the virus-host relationship are discussed. 相似文献