An immunoistochemical (IHC) test was developed to detect bovine respiratory syncytial virus (BRSV) in cell cultures and tissues of experimentally infected mice and calves, using a commercial monoclonal antibody (Mab) against human respiratory syncytial virus (HRSV), as a less expensive alternative, instead of producing specific monoclonal antibodies to BRSV. Clinical samples from calves suffering respiratory disease were also submitted to this test. IHC detected BRSV antigens in mouse tracheas (3, 5 and 7 days post-infection) and lungs (5 and 7 days post-infection), and in one of three lungs from experimentally infected calves. Lungs samples from two naturally infected calves were tested and resulted positive for BRSV by the IHC test. These results suggest that this test may be used in the future for diagnosis as well as a useful tool to assess the distribution of BRSV infections in Brazilian herds.