Growth and Characterization of the Virus of Bovine Malignant Catarrhal Fever in East Africa

Abstract

SUMMARYA strain of bovine malignant catarrhal fever virus (MCF) recovered from the blood of a blue wildebeest was developed by passage in vitro to a stage where it could be propagated serially in primary thyroid cell cultures by inoculation of cell-free fluids. Released virus titres ranged from 103.8 to 105.8 50% tissue culture infectious doses/ml. This virus still caused fatal disease when inoculated to cattle, and was neutralized by antibody that appeared in the sera of cattle recovering from experimental infection. The principal cytopathic effects of the virus were the development of DNAcontaining intranuclear inclusions and syncytia ; the inclusions became increasingly basophilic as they matured. The cytopathic effects were inhibited in the presence of 5-iodo-2'-deoxyuridine (IUDR), and infectivity of the virus was abolished by treatment with ether or chloroform. Electron microscopy of inoculated cell cultures showed intranuclear, cytoplasmic and extracellular herpes-like virus particles. Suspensions of cell-free virus examined by negative-stain electron microscopy contained some particles of diameter 140 mp-220 mp, comprising an outer envelope and a central body or capsid; others consisted of only a naked capsid about 100 mp in diameter. MCF virus is evidently a member of the herpes group, and has particular affinities to a subgroup which contains the agents of varicella, herpes zoster and the cytomegaloviruses.

Characteristics of Bovine Mammillitis Virus

“…BMV is therefore identified as another bovine member of the family of herpesviruses. Like other bovine herpesviruses, it produces syncytia and intranuclear inclusions in cultured cells, It resembles IBR virus (Armstrong,Pereira & Andrewes,19Sl), but differs from most lines of MCF virus (Plowright, Macadam & Armstrong, 1965) in its relative ease of cultivation and its release in significant amount from infected cells into the culture fluid. The serological reactions of BMV separate it clearly from these and other herpesviruses, with the exception of the Allerton prototype strain of the group I1 viruses of lumpy skin disease (Alexander et al 1957), from which it cannot be distinguished in standard neutralization and agar-precipitation tests.…”

Isolation and identification of malignant catarrhal fever virus in cell cultures

“…Plowright et al (1963), Plowright (1968, Castro et al (1982) have found big syncytia and inclusion bodies in bovine embryonic testis cells and bovine foetal kidney of isolates originating from an Indian gaur and Greater kudu with typical clinical signs of MCF. We have observed growing of infected MDBK cell culture with samples from organ suspensions from gaur (Fig.…”

Bovine Cytomegaloviruses: Identification and Differential Properties

“…Mammillitis and skin disease are induced by BHV-2 (Martin et al, 1966). Antelope-associated bovine malignant catarrhal fever (MCF) in Africa was proven to be caused by BHV-3 (Plowright et al, 1960(Plowright et al, , 1965. Herpesviruses were isolated from lungs of sheep (Malmquist et al, 1972;De Villiers et al, 1975), and these isolates were later categorized as BHV-5 by De Villiers (1979).…”