A serologic survey of bovine rotavirus infection in Italy.

Serum neutralization tests conducted by microtiter procedure on 2970 serum samples from calves, heifers and adult cows from representative regions of Italy indicate that rotaviruses, and the infection which they cause, existed in Italy long before the virus was isolated. At the present time the infection is distributed fairly uniformly throughout the cattle population with both sexes and all age groups being equally susceptible.

Characterization of a caprine herpesvirus.

A virus, which was isolated from kids (Capra hircus) affected with a relatively severe generalized infection, was found to contain DNA and to have a buoyant density of 1.2820 g/cm3. The virus was sensitive to the action of lipid solvents and trypsin and was rapidly inactivated at pH 3.0 and at temperatures of 50 and 56 C. The virion, an icosahedron consisting of a nucleoid surrounded by a double membrane, measured approximately 135 nm in diameter. On the basis of its chemical and physical properties, the virus is considered a herpesvirus.

Pathogenicity of a caprine herpesvirus.

A herpesvirus isolated from neonatal Angora kids (Capra hircus) with a relatively severe generalized infection was shown to be infective for adult goats as well as for kids. However, the virus lacked pathogenicity for either lambs or calves. Although a nonreciprocating serologic overlap exists between the caprine virus and the antibody to bovine herpesvirus (BHV-1), results of cross immunity tests in calves indicated that the 2 viruses are immunologically distinct. On the basis of these findings, the caprine virus seems to be a specific pathogen of goats. Accordingly, the designation of Herpesvirus caprae or caprine herpesvirus 1 seems taxonomically appropriate.

Preliminary characterization and pathogenicity studies of a virus isolated from ticks (Ornithodoros coriaceus) and from tick-exposed cattle.

Several viral isolates from ticks (Ornithodoros coriaceus) and from the blood of cattle which aborted after exposure to these ticks were found to be identical by reciprocal cross serum-neutralization tests. Characterization studies indicate that the virus is a member of the Togaviridae family, although specific identification is still incomplete. Whether its natural host is the tick or bovine animals is also unknown. Pregnant cows inoculated with the agent by all conventional parenteral routes, including intrafetal, delivered healthy calves at term. It was concluded, therefore, that it was not a bovine pathogen and that the abortions which occurred after tick-exposure were due to a 2nd agent in O coriaceus ticks which also harbor the virus. While several ciruses believed to be tick-borne have been isolated from cattle in various parts of the world, it is believed that the present report describes the first isolation in the Western Hemisphere for a viral agent from Argasid ticks which has been demonstrated to replicate in cattle.

Preliminary studies on transmission of Chlamydia to cattle by ticks (Ornithodoros coriaceus).

Preliminary findings indicate that Ornithodoros coriaceus ticks can harbor Chlamydia for long periods and are able to transmit the agent to cattle. Field-collected O coriaceus ticks, which were infected experimentally with a bovine chlamydial agent from an aborted fetus, transmitted the agent 25 and 48 days later to three pregnant heifers. Two of these heifers aborted and the third delivered a term calf. The control heifer also aborted after intradermal (simulated tick) exposure. Also, a chlamydial agent was isolated from field-collected O coriaceus ticks in an epizootic bovine abortion (EBA)-enzootic area that were held for at least 6 months. In the same enzootic area, a chlamydial agent was isolated from a prematurely delivered calf during a severe EBA outbreak. Seemingly, this species is a cause, if not the cause, of EBA.

Viral agents recovered from Ornithodoros coriaceus, a vector of epizootic bovine abortion.

Two unidentified viral isolates from the tick, Ornithodoros coriaceus, the probable vector of the causative agent of epizootic bovine abortion, did not cause any untoward reactions in pregnant heifers which were experimentally inoculated or which were exposed to bites of O coriaceus that had been infected with cultures of the two isolates. Seemingly, neither viral isolate is involved in the cause of epizootic bovine abortion.

Prevalence of pseudorabies in sows in central Illinois.

Of 1,224 serums from slaughtered sows from central Illinois, 52 (4.25%) were found to be positive for pseudorabies neutralizing antibody.