In vitro isolation and identification of the first Neospora caninum isolate from European bison (Bison bonasus bonasus L.)

Peripheral blood from European bison (Bison bonasus bonasus L.) living in Białowieża Forest, north-east Poland, were investigated for the presence of antibodies to Neospora caninum and isolation of parasite. Out of 23 animals three of them showed a strong positive response to N. caninum (13%).The white blood cells from two positive and two negative bison were loaded on monolayer Vero cells culture. The first viable tachyzoites were detected only in positive samples at days 60 and 70 after incubation.For the purpose of the identification the isolates, tachyzoites were evaluated by PCR and sequence analysis of fragment of the Nc-5 region.The sequences of N. caninum-specific Nc5 region were found to be identical to those of other N. caninum isolates found in the public database. The isolate was subsequently named NC-PolBb1 and NC-PolBb2.This is the first record of in vitro isolation of N. caninum from naturally infected European bison (Bison bonasus bonasus L.) and the first isolate obtained from the peripheral blood.