Occurrence of anti-Neospora caninum antibodies in cattle in the dairy farming region of the state of Piauí, Brazil oleh Raylson Pereira de Oliveira, Nínivy Marques Soares, José Givanildo da Silva, Müller Ribeiro-Andrade, Nair Silva Cavalcanti de Lira, Márcia Paula Oliveira Farias, Rinaldo Aparecido Mota