Experimental intravaginal infection of goats with caprine herpesvirus 1

Three adult goats, seronegative to caprine herpesvirus 1 (CpHV.1), were intravaginally inoculated with BA.1 strain of CpHV.1. The animals were kept under observation for 1 month and daily both clinical examinations and white blood cell count were performed. Ocular, nasal, rectal and vaginal swabs and heparinized blood samples were collected every day to attempt virus isolation on cell cultures and detect viral DNA by polymerase chain reaction (PCR) assay. The virus was isolated and detected by PCR only from the vaginal swabs for 5-7 days post-infection. The animals showed transient fever and leukopenia and typical necrotic lesions on the vulva and vagina.     

Experimental respiratory infection of goats with caprine herpesvirus and Pasteurella haemolytica

Groups of six male goats were inoculated intratracheally and intranasally with either caprine herpesvirus followed 6 days later by Pasteurella haemolytica, canine herpesvirus alone or P. haemolytica alone. Pneumonic lesions were observed in five of the six goats inoculated with caprine herpesvirus followed by P. haemolytica and in three of the six goats inoculated with P. haemolytica alone, but were not observed in goats inoculated with caprine herpesvirus alone or in non-infected controls. Pasteurella haemolytica was isolated from seven of eight lungs with pneumonia, but only from one of sixteen lungs without pneumonia. The lesions ranged from fatal acute exudative necrotising pneumonia to predominantly proliferative pneumonia. Half of the caprine herpesvirus-inoculated goats developed a clinical catarrhal rhinitis five days post-inoculation and the only virus-specific histopathological lesion was a mild tracheitis. Canine herpesvirus was recovered from the nasal swabs of all caprine herpesvirus- inoculated goats developed a clinical catarrhal rhinitis five days post-inoculation and the only virus-specific histopathological lesion was a mild tracheitis. Canine herpesvirus was recovered from the nasal swabs of all canine herpesvirus-inoculated goats and from the lungs of three goats inoculated with caprine herpesvirus alone. The experimental inoculations demonstrated that P. haemolytica alone can produce pneumonia in goats. In addition, the study showed that caprine herpesvirus readily proliferates in the upper respiratory tract and lungs of goats but the role of caprine herpesvirus in the aetiology of pneumonia remains uncertain.     

Reactivation of caprine herpesvirus 1 in latently infected goats

The authors report CapHV.1 reactivation in two latently infected adult goats treated with dexamethasone (DMS) (4.40 mg/kg BW) for 6 days. Virus was reisolated from vaginal swabs from the 3rd to the 12th day post-treatment with DMS and from nasal swabs for 2 days (6th and 7th day post-treatment). The animals also showed an increase of neutralizing antibody (SN) titer to CapHV.1 3 weeks after the end of treatment with DMS.     

A live attenuated glycoprotein E negative bovine herpesvirus 1 vaccine induces a partial cross-protection against caprine herpesvirus 1 infection in goats

Taking into account the close antigenic relationship between bovine herpesvirus 1 (BoHV-1) and caprine herpesvirus 1 (CpHV-1), a live attenuated glycoprotein E (gE) negative BoHV-1 vaccine was assessed in goats with the aim to protect against CpHV-1 infection. Vaccine safety was evaluated by intranasal inoculation of two groups of goats with either a gE-negative BoHV-1 vaccine or a virulent BoHV-1. The length of viral excretion and the peak viral titre were reduced with the gE-negative vaccine. To assess the efficacy, two goats were inoculated intranasally twice 2 weeks apart with a gE-negative BoHV-1 vaccine. Four weeks later, immunised and control goats were challenged with CpHV-1. A 2 log(10) reduction in the peak viral titre was observed and the challenge virus excretion lasted 2 days more in immunised than in control goats. These data indicate the safety and the partial efficacy of a live attenuated gE-negative BoHV-1 vaccine intranasally administrated in goats.     

Transmission of caprine herpesvirus 2 in domestic goats

Caprine herpesvirus 2 (CpHV-2) is a recently recognized gammaherpesvirus that is endemic in domestic goats and has been observed to cause clinical malignant catarrhal fever (MCF) in certain species of deer. In this study, transmission of CpHV-2 in goats was examined. A total of 30 kids born to a CpHV-2 positive goat herd were selected and divided into two groups: group 1 (n=16) remained in the positive herd; group 2 (n=14) was separated from the herd at 1 week of age after obtaining colostrum. Peripheral blood samples from each kid were examined regularly by competitive ELISA for MCF viral antibody and by PCR for CpHV-2 DNA. Fifteen out of 16 goats (94%) that remained with the positive herd seroconverted and became PCR-positive for CpHV-2 by 10 months of age. In contrast, all kids (100%) that were separated from the positive herd at 1 week of age remained negative until termination of the experiment at 1 year of age. Additional transmission experiments revealed that all CpHV-2-free adult goats were susceptible to CpHV-2 or ovine herpesvirus 2 (OvHV-2) infection. The data indicate that the transmission pattern of CpHV-2 in goats is similar to the pattern of OvHV-2 in sheep and that CpHV-2-free goats can be established by early separation of kids from positive herds, which has significant implications for MCF control programs.     

Serological evidence of caprine herpesvirus 1 infection in Mediterranean France

Caprine herpesvirus 1 (CpHV-1) is responsible of a systemic disease in kids and genital diseases inducing abortions in adult goats. In Europe, CpHV-1 is widespread in Mediterranean countries such as Greece, Italy and Spain. As France is geographically close to these countries, a survey was conducted to investigate the presence of CpHV-1 in goats in a Mediterranean department (Corse-du-Sud) and in continental departments (Dordogne and Vendée) of this country. Taking into account the close antigenic and genetic relationships between bovine herpesvirus 1 (BoHV-1) and CpHV-1, the serological detection was performed by using BoHV-1 glycoproteins B (gB) and E (gE) blocking ELISAs. The analysis of 2548 serum samples in a BoHV-1 gB blocking ELISA revealed that a ruminant alphaherpesvirus infection related to BoHV-1 was widespread in Corse-du-Sud whereas no positive animals was detected in Dordogne and Vendée. Furthermore, the specificity and the sensitivity of the BoHV-1 gB blocking ELISA to detect a BoHV-1 related infection in goats were evaluated. A subsequent analysis by a BoHV-1 gE blocking ELISA demonstrated that 22.6% of gB-positive serum samples were also gE-positive. Cross-seroneutralisation assays afforded the unambiguous identification of antibodies against CpHV-1 in gB-positive goats. The likely presence of CpHV-1 in Corse-du-Sud supported by a high seroprevalence (61.9%) in all investigated flocks extends the number of countries infected with CpHV-1. Moreover, the difference observed between Corse-du-Sud and Dordogne and Vendée suggests that CpHV-1 is more prevalent in Mediterranean countries or regions than in central and northern Europe.     

Experimental infection of possums with macropodid herpesvirus 1

AIM: To determine whether macropodid herpesvirus 1 (MaHV-1) could infect brushtail possums (Trichosurus vulpecula) and whether such infection would lead to latency in possums. METHODS: Possums (n=9) were instilled with 1.9 x 10(8) TCID50 of MaHV-1 into the conjunctivae and nostrils, while controls (n=3) were administrated with sterile saline. For virus isolation, all possums were swabbed from the conjunctivae and nasal cavities prior to inoculation, and on Days 1, 3, 7, 10 and 14 post-inoculation (p.i.), and then at weekly intervals for up to a further 6 weeks. Sera were collected on Day 0 immediately prior to inoculation and fortnightly thereafter, for the measurement of antibody. Corticosteroids were administrated to 4/9 virus-inoculated possums on Days 36 and 41 p.i. to determine whether latent MaHV-1 infection could be reactivated. Trigeminal ganglia and other tissues were collected at necropsy for viral detection. A nested polymerase chain reaction (PCR) targeting the DNA-dependent DNA polymerase (DNA pol) gene of the herpesviruses using degenerate primers was conducted on DNA samples isolated from the ganglia and livers from the possums, and blind-passaged cell cultures, for viral detection. RESULTS: A mild conjunctivitis was observed in the majority of the virus-inoculated possums between Days 3 and 21 p.i. Virus was recovered from the conjunctiva and/or nasal swabs from 8/9 virus-inoculated possums on Days 1 and 3 p.i. and from 3/9 on Day 7 p.i., but not following administration of corticosteroids. No virus was recovered from the trigeminal ganglia of the virus inoculated possums and possum DNA samples were negative for viral DNA following nested PCR. All of the virus-inoculated possums produced a virus neutralisation antibody response by Day 28 p.i., and five had a titre >/=512. The sequence of a 133 base pair (bp) segment of the MaHV-1 DNA pol gene was considerably different from that of other published data. CONCLUSION: This study demonstrated that MaHV-1 might have established a transient infection at the inoculation sites, and the inoculation of MaHV-1 via intranasal and conjunctival routes could elicit MaHV-1-specific antibody responses in possums. However, systemic and latent infection of MaHV-1 in possums was not demonstrated.     

An outbreak of vulvovaginitis in goats caused by a caprine herpesvirus

A caprine herpesvirus related to infectious bovine rhinotracheitis virus but immunologically distinct from that virus was isolated from an outbreak of vulvovaginitis in a herd of Saanen goats. The morbidity rate was 52.5%, with 21 of 40 does showing clinical signs. The lesions healed rapidly with only two goats showing lesions two weeks after the disease was first detected. No effect on subsequent reproductive performance was observed. The mode of transmission of the virus was believed to be venereal.     

An outbreak of vulvovaginitis in goats caused by a caprine herpesvirus

A caprine herpesvirus related to infectious bovine rhinotracheitis virus but immunologically distinct from that virus was isolated from an outbreak of vulvovaginitis in a herd of Saanen goats. The morbidity rate was 52.5%, with 21 of 40 does showing clinical signs. The lesions healed rapidly with only two goats showing lesions two weeks after the disease was first detected. No effect on subsequent reproductive performance was observed. The mode of transmission of the virus was believed to be venereal.     

Isolation of caprine herpesvirus 1 from a major outbreak of infectious pustular vulvovaginitis in goats

We describe an outbreak of infectious pustular vulvovaginitis caused by Caprine herpesvirus 1 (CpHV1) in a group of approximately 200, 8 month old virgin does that were imported to Victoria from New Zealand. CpHV1 was isolated in cell cultures from vaginal swabs from three of three affected does but not from two bucks that had been with the does. The identity of the virus as a herpesvirus was confirmed by negative stain electron microscopy. Restriction endonuclease DNA fingerprint analysis showed that the DNA fingerprints were similar, but not identical, to previously described CpHV1 isolates made in New Zealand, New South Wales, and in other parts of the world. Acute and convalescent phase sera from selected does supported the diagnosis of CpHV1 infection. It is most likely that the disease was initiated by reactivation of latent virus in at least one of four bucks that served the does, since each was positive for CpHV neutralising antibody when first tested. This is the first report of CpHV infectious pustular vulvovaginitis in goats in Victoria and to our knowledge appears to be one of the largest outbreaks recorded anywhere.     

Antigen-specific IFN-gamma and IL-4 production in caprine herpesvirus infected goats

The analysis of cytokines secreted by antigen-specific lymphocytes is hampered in goats by the paucity of species-specific reagents yet it is crucial to study immune responses to infections. To overcome this limit, two commercial kits designed to measure soluble bovine IL-4 (by ELISA) and frequencies of bovine IFN-gamma secreting cells (by ELISPOT) were tested for cross-reactivity in goats. In addition, an ELISA specific to bovine/ovine IL-4 and employing two monoclonal antibodies, clones CC313 and CC314, was tested as well. Concanavalin A-stimulated caprine peripheral blood mononuclear cells (PBMCs) cultures were studied and they exhibited high levels of soluble IL-4 and high frequencies of IFN-gamma secreting cells. In addition, the two IL-4 ELISAs detected similar amounts of cytokine. To start defining the cytokine response triggered by caprine herpesvirus 1 (CpHV-1) infection, PBMC cultures were setup from goats naturally or experimentally infected with CpHV-1. High frequencies of IFN-gamma producing cells and low, when detectable, levels of soluble IL-4 were observed in CpHV-1-specific PBMC cultures from both groups of infected goats. Thus, the availability of cross-reactive research tools can expand cytokine studies in goats and can implement the research on immunity to other caprine infections.     

Experimental infection of sheep by caprine arthritis-encephalitis virus and goats by progressive pneumonia virus

The lentiviruses, caprine arthritis-encephalitis virus (CAEV) and progressive pneumonia virus (PPV) of sheep, cause major diseases in their respective hosts; however, the infectivity of these viruses for closely related species has not been determined. Experiments were conducted to determine whether CAEV would infect sheep and whether PPV would infect goats. Upon inoculation with CAEV, lambs developed a nonsuppurative arthritis and antibody to CAEV, and the virus was isolated up to 4 months later. Exposure of 3 lambs to CAEV-infected adult goats did not lead to demonstrable infection after 18 months. Young goats inoculated with PPV replicated the virus and developed arthritis and antiviral antibody. These results demonstrate that these distinctly different lentiviruses may infect and cause diseases in species other than their accustomed host. Presently used techniques may not be effective in differentiating which lentivirus is responsible for infection of sheep and goats. Our results also indicate that mixing sheep and goats may adversely influence attempts to eradicate lentiviruses from these species.     

Abortion and ulcerative posthitis associated with caprine herpesvirus-1 infection in goats in California.

Three outbreaks of late-gestation abortions in does and ulcerative posthitis in bucks, associated with caprine herpes virus-1 (CHV-1), in California are described. In herd A, 10 of 17 does aborted in a 7-day period, whereas in herd B, 4 of 130 does aborted in a 45-day period and in herd C, 100 of 300 does aborted in a 3-week period. Most fetuses had multifocal pinpoint depressed foci with a zone of hyperemia on external and cut surfaces of the kidneys, liver, lungs, and adrenal glands. Histologically, scattered multifocal areas of necrosis with mild neutrophilic infiltrate were observed in kidneys, brain, liver, adrenal glands, and lungs of most fetuses of the 3 herds. Large amphophilic intranuclear inclusion bodies, which displaced the chromatin, were observed in cells within and around the necrotic foci in kidneys and adrenal glands. Particles 85-113 nm in size with morphology compatible with herpes virus were observed in the nuclei of these cells when examined by electron microscopy. Irregular, shallow, red ulcers were observed in the prepuce of 1 buck from herd C. Prepuce biopsies from this animal had necrosis of the superficial mucosal epithelium and severe submucosal lymphoplasmocytic infiltrates. Large intranuclear amphophilic inclusion bodies were observed in most cells of the stratum spinosum of the preputial epithelium, but no viral particles were observed in these cells. Caprine herpes virus-1 was isolated from tissue pools of fetuses from the 3 herds but not from prepuce biopsies. Positive results were obtained when tissues of a fetus from herd C were processed by a polymerase chain reaction technique to amplify the amino terminus of the glycoprotein C gene of CHV-1. Sera from aborted does from herds B and C and from the 3 bucks from herd C had high antibody titers to CHV-1. The results presented here support the hypothesis that the male goat is involved in the transmission of CHV-1. However, other forms of transmission cannot be ruled out.     

Effects of infection with caprine arthritis-encephalitis virus on milk production in goats

A recently assembled commercial herd of Alpine goats was studied. Milk production criteria--305-day milk production (M), butter fat content (BF), and solids nonfat content (SNF)--and somatic cell counts (linear score) were monitored by Dairy Herd Improvement Association test records. Milk samples from all milking goats in the herd were obtained for bacteriologic culture for mastitis organisms on 2 occasions; the infection rate ascribed to major pathogens was 3%. In November 1985, serum specimens were obtained from 154 does in first lactation. Of these, 56 (36%) were seropositive for caprine arthritis-encephalitis (CAE) antibodies by agar gel immunodiffusion (AGID), 91 (59%) were seronegative, and serotest results for 7 (5%) were inconclusive. In December, 80 seronegative and 48 seropositive goats remained in the herd and had 305-day projections available. The median production values for seronegative goats (1,539.5 lb of M, 52 lb of BF, 46 lb of SNF) were higher than those for seropositive goats (1,446 lb of M, 45 lb of BF, 44.5 lb of SNF), but this difference was only significant (t test, P less than 0.05) for BF. Does were ranked by a formula that combined M, BF, and SNF, with a desired minimal daily herd average of 5 lb of M, 3% BF, and 3% SNF. A decision was made not to keep offspring from does of the lowest quartile before CAE test results were obtained. This group consisted of 13 of the 80 (16%) seronegative goats and 18 of the 48 (38%) seropositive goats. Thus, a positive CAE test result by AGID was associated (chi 2, P less than 0.01) with poor production.(ABSTRACT TRUNCATED AT 250 WORDS)     

Isolation of caprine herpesvirus type 1 in Spain

Two strains of caprine herpesvirus type 1 (CpHV-1) were isolated after the experimental reactivation of two seropositive goats in Spain. Viral DNA from these isolates was compared with DNA from bovine herpesvirus type 1 and CpHV-1 reference strains by restriction endonuclease analysis. The two Spanish isolates were closely related but could easily be distinguished from each other and from the reference strains.     

Transplacental BVD virus transmission after experimental inoculation of goats in different pregnancy stages

Eight groups of altogether 25 goats without neutralizing antibodies against BVD virus, were inoculated either intranasally or intranasally and subcutaneously with two different BVD virus isolates during different stages of gestation. In all 18 goats inoculated within the first 78 days of gestation an abortion and foetal death rate of approximately 100% occurred. Only one goat gave birth to a clinically healthy kid. The other seven goats which were inoculated after the 78th day of gestation showed also a high foetal death rate. Only two of them gave birth to clinically healthy kids. Neutralizing antibodies against BVD virus could be detected in blood samples drawn from 14 kids born at normal term including stillborn and non-viable offsprings. BVD virus was reisolated from different organs taken from seven foetuses. It was not possible to isolate BVD virus from any of the normal offsprings.     

Experimental infection of goats with Brucella ovis

Six goats were inoculated with Brucella ovis. Two goats were inoculated with infected semen by the intratesticular route and 2 each by installation of the semen on to the nasal or preputial epithelium. All goats produced antibody responses as measured by an enzyme-linked immunosorbent assay (ELISA) procedure and the serums of 5 goats reacted in complement fixation tests for B. ovis. The 2 goats inoculated by the intratesticular route and one receiving B. ovis instilled intranasally subsequently excreted B. ovis in their semen. The possibility of natural transmission is discussed.