Abstract
Two strains, the Bibuna and the Bucyrus, of equine arteritis virus (EAV) were tested for propagation in various cell cultures. They were grown in primary cell cultures of horse, rabbit, hamster, cat and pig kidney, and in established cell cultures of baby hamster kidney (BHK-21/13), hamster lung (HmLu), African green monkey kidney (Vero) and Cynomolgus monkey kidney (JINET). Cytopathic changes were comparatively common to all cells, and characterized by rounding and vacuolation of the cells and by increased density of the cytoplasm. Most affected cells were detached from the glass wall within 7 days after inoculation. The infectivity titers of the primary cell culture fluids were 104 to 106 TCID50/0.2 ml, and those of the established cell culture fluids 106 to 108 TCID50/0.2 ml. Both strains were able to replicate in the presence or absence of 5-iodo-2-deoxyuridine (IUDR). They were not stabilized by cation at 50°C, but were highly sensitive to ether and sodium deoxycholate, and moderately sensitive to heat and acid. The Bibuna strain was more sensitive to a high concentration of trypsin than the Bucyrus strain. Each virus formed distinct piadues 2 to, 3 mm in diameter on the monolayer of Vero cells. Serum samples were collected from 107 horses in Japan in 1972 and 1978 and tested for EAV antibody by neutralization tests in monolayer cell culture tubes or plaque reduction neutralization tests in Vero cells. No antibody, however, was detected from any sample so far.
