The Morphogenesis and Biology of a Morbillivirus from MCF Cattle

Cell-associated syncytiogenic viruses were previously isolated from a calf (72-P-535) with experimentally induced malignant catarrhal fever. The isolate recovered from leukocytes was investigated by studying its growth and cytopathology in low passage fetal bovine cells. Antigenic studies with this virus and other 72-P-535 isolates using direct and indirect immunofluorescence techniques revealed that each isolate was related to agents of the measles, canine-distemper, rinderpest group. The 72-P-535 leukocyte isolate induced polykaryons in several fetal bovine cell types but not in HeLa, VERO or mouse L-cells. Neither nuclear nor cytoplasmic inclusions were detected in Giemsa-stained coverslip preparations of infected cells. Guinea pig, human 'O' and bovine erythrocytes were not agglutinated by cell-free culture fluids or cell lysates nor did they absorb to infected cells.