In vitro isolation and characterization of bovine Neospora caninum in Korea

The brains of nine aborted bovine fetuses and two newborn calves born from dams suspected to be infected with Neospora caninum were homogenized and in oculated into Vero cells. All fetuses and calves were from cows determined as seropositive to N. caninum by an IFA test. Sera and thoracic fluids of a ll fetuses and calves also revealed high antibody titer to N. caninum by IF AT ranging from 1:800 to 1:3200. N, caninum was isolated from the brains of one aborted fetus and one newborn calf when the brain homogenates were gro wn continuously in Vero cell culture. N. caninum tachyzoites, giemsa-positi ve, were first observed on Days 45 and 56 postinoculation in the newborn ca lf and the aborted fetus, respectively. The isolates (KBA-1 and KBA-2) were morphologically and ultrastructurally similar to previously published Neos pora isolates. The isolated parasites were confirmed as N. caninum by means of the antigenic reactivities, immunostaining, PCR and southern blotting, and electron microscopy. (C) 2000 Elsevier Science B.V. All rights reserved .