Infection by Neospora caninum associated with bovine herpesvirus 1 and bovine viral diarrhea virus in cattle from Minas Gerais State, Brazil

Neospora caninum is a canine parasite which is considered a significant cause of bovine abortion. Two cattle herd groups were serologically studied with the objective of studying the prevalence of infection by N. caninum associated with BHV1 and BVDV infections. In group I, 15 dairy herds (476 samples) naturally infected by the three infectious agents were analyzed,. In group II, three dairy herds (100 samples) of cows vaccinated for two viruses were analyzed, in order to determine the infection prevalence by N. caninum. In the first group, an infection prevalence of 12.61, 34 and 28.3% was determined for N. caninum BHV1 and BVDV, respectively. In the second group, a seropositive prevalence of 46, 85 and 76%, respectively, was determined for N. caninum, BVH1 and BVDV. In the first group, the virus and N. caninum had shown in the first group 4.41% positive samples in association with BVH1, 3.15% with BVDV, and 8.41% with BVH1 and BVDV.