Studies on infectious pustular vulvovaginitis virus with particular reference to the genital disease in bulls
Viruses have been implicated as a cause of bovine genital disease by workers in several countries. Recently attention has been focused on one such disease which has been defined as an acute, specific, viral infection of cattle affecting the vulva and vagina of the female and the penis and prepuce of the male and characterised first by pustules, later by ulceration of the affected mucous membrane. The lack of precise knowledge concerning many facets of this disease is exemplified by the variety of synonyms which have been used in the past: vesicular venereal disease, vesicular vaginitis, coital exanthema, coital vesicular exanthema, genital cowpox. In Europe the term Blaschenausschlag is used. The inadequacy of this nomenclature may be illustrated by three pertinent facts: (a) Witte (1933) demonstrated that at no stage was the lesion vesicular and this author suggested the term exanthema pustulosum coitale. (b) North American experience, contrary to that of European workers has shown that most outbreaks of the disease are not related to coitus, (c) exanthema strictly applies to eruptions of the skin (Gould, 1956). Although the term infectious pustular vulvovaginitis (IPV) introduced by Kendrick et al. (1958) circumvents several of these misnomers, acceptance of this term poses the problem of designating the disease in the bull. Other viruses have been found associated with bovine genital diseases but the syndromes described do not resemble IPV. These viruses include: a virus isolated from a catarrhal vaginitis in the USA (Kendrick et al., 1956). In South Africa Mcintosh et al. (1952) have isolated a virus from outbreaks of vaginitis (the relationship of this virus to infectious bovine infertility (epi-vag) is uncertain). In England (Millar, 1955) suspected a virus as a cause of infertility. McClure (1956, 1957) in New Zealand also proposed that a virus was associated with vaginitis and lowered fertility in some herds. In Canada an outbreak of an acute vaginitis in a herd of cattle in southern Ontario was observed in 1955; vaginal exudate collected from affected animals reproduced a similar disease tdien inoculated into the vagina of heifers (Barker, 1953). From the same vaginal exudate a cytopathogenic agent was isolated in foetal bovine skin and foetal bovine kidney tissue cultures and tissue culture fluid containing the agent reproduced the disease when inoculated into heifers (Grieg et al., 1953). There are few detailed reports of infection of bulls with IPV virus and the present study has been primarily concerned with this aspect. Consideration has been given to the Infectivity infection of other species of domestic animal, and some of the fundamental properties of the infectious agent. Recently it has been demonstrated that IPV virus is indistinguishable from the agent which causes infectious bovine rhinotracheitis (IBR) (Gillespie et al., 1959; McKercher et al., 1959). Although IPV is not considered to be an important disease by most authorities, the economic importance of IBR is well established. For this reason it becomes necessary to have considered in full the disease producing potential of the aetiological agent. More importantly the interrelationship of these conditions from an epizoological viewpoint is basic to an understanding of both.