Corticoid activation of infectious bovine rhinotracheitis virus--infectious pustular vulvovaginitis virus (IBR-IPV)]

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.     

Round table on infectious bovine rhinotracheitis/infectious pustular vulvovaginitis virus infection diagnosis and control

The current situation of infectious bovine rhinotracheitis/infectious pustular vulvovaginitis infection in various European countries is reviewed. Whilst some have a high serological prevalence and use live virus vaccines to control the disease, others have a low prevalence and two countries (Denmark and Switzerland) have national eradication schemes which are almost complete. Serology remains important for diagnosis although other tests such as delayed cutaneous hypersensitivity may have a role to play. New tests such as polymerase chain reaction may find increasing application where high sensitivity is required, such as the detection of virus in semen.     

The isolation of a cytopathogenic agent resembling the virus of infectious bovine rhinotracheitis from an outbreak of pustular vulvovaginitis in cattle

Two hundred and twenty seven dairy cows and heifers which had conceived at least 245 days previously were treated with dexamethasone alone (20 mg i/m), cloprostenol alone (500 µg s/c) or both drugs at different time-combinations in order to study the effect in terms of induction of parturition.

Results showed that cloprostenol alone, or 8–11 days after dexamethasone, caused 81% and 96% of animals respectively to calve within 1–4 days of the cloprostenol treatment.

Dexamethasone alone or injected on the same day as cloprostenol also advanced the day of calving but both spread and delay were longer than with the othertreatments.

Animals treated with cloprostenol alone, or cloprostenol 8–11 days after dexamethasone, showed oestrous behaviour 24 hours before calving, though without adverse results. Calf survival was similar for all treated groups. Cloprostenol treatments were associated with a higher incidence of retained foetal membranes (28.2–5.7%) but also with a shorter interval from parturition to resumption of cyclicity.     

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis viral isolates from cattle with epididymitis and vaginitis.

Infectious bovine rhinotracheitis-infectious pustular vulvovaginitis (IBR-IPV) viral isolates were obtained from cattle affected with epididymitis-vaginitis. Isolation of virus from the diseased animals indicated that the genital form of IBR-IPV virus infection exists in Kenya and that epididymitis-vaginitis may be associated with IBR-IPV virus. Serums prepared from cattle having the genital form of the disease did not always have detectable antibody titers.     

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.