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
.