Serological profile of infectious bovine rhinotracheitis, bovine viral diarrhea, leptospirosis, toxoplasmosis, and neosporosis in beef cattle herds in Tocantins, Northern Brazil.

Monitoring the health of cattle herds is essential for establishing prophylactic measures and reducing their impact on the production chain, especially in regions where beef cattle form the economic base. This study aimed to determine the serological profile of infectious bovine rhinotracheitis (IBR), bovine viral diarrhea (BVD), leptospirosis, toxoplasmosis, and neosporosis in beef cattle slaughtered in a federally inspected slaughterhouse in the state of Tocantins, northern Brazil. A total of 614 serum samples from 70 herds were evaluated for the presence of antibodies to Bovine alphaherpesvirus-1 and Bovine viral diarrhea virus by virus neutralization test, 12 serovars of Leptospira spp. by microscopic agglutination test, and to Toxoplasma gondii and Neospora caninum by indirect immunofluorescence reaction. The rates of seropositive animals for IBR, BVD, leptospirosis, toxoplasmosis, and neosporosis were 90.4, 50.8, 63.2, 6.2, and 7.3%, respectively. For herds, 100% had at least one animal serum positive for IBR and leptospirosis. Considering the seropositive rates for the five infectious diseases observed in slaughtered cattle, the number of beef cattle in Tocantins, and the intrinsic conditions of the etiological agents being by regional seasonality, it is essential to implement or improve animal health surveillance, prevention, and biosecurity programs to ensure better productivity and economic sustainability of beef cattle herds in the state.