The objective in the present study was to research the prevalence of anti-Neospora caninum in 812 samples of blood serum of dairy cattle from farms of seven municipalities of microrregions of Itapecuru-Mirim, Middle Mearim and President Dutra, state of Maranhão, Brazil. For the calculation of sample size, it was considered a seroprevalence of 34.7% for N. caninum, with a maximum error of 9.5% and a confidence interval of 95%. To detect antibodies, it was used the technique of Indirect Immunofluorescence (IFI), with the cut-off of 1:200, using as antigen, tachyzoites strain NC-1, maintained in cell culture in the Laboratory of Diagnosis of Parasitism of the Animals, School of Veterinary Medicine of the Federal University of Bahia, Brazil. Of the total samples, it was obtained a prevalence of 50.74%. The titles ranged from 1:200 to 1:6400, distributed as follows: 108 (26.21%) serum samples showed title of 1:200; 132 (32.04%) 1:400; 94 (22.81%) 1:800; 46 (11.16%) of 1:1600; 23 (5.58%) of 1:3200 and nine (2.18%) with titers of 1:6400. Among the microrregiões the Itapecuru-Mirim showed the lowest percentage of animals seropositive (20.69%) and President Dutra the largest (47.66%). It was observed higher prevalence of seropositives in females (46.80%) than in males (52.46%). There was no significant difference (P> 0.05) for the microrregions variables, sex and age. Concluded that the dairy cattle of the regions studied are exposed to infection by N. caninum.
Neospora caninum; prevalence; bovine neosporosis; Maranhão
