Investigation of Parainfluenza Virus Type 3 (BPIV3) in Cattle Using Direct Immunfluorescence (DIF) Test and Reverse Transcriptase - Polymerase Chain Reaction (RT-PCR) Technique

Sampling was obtained from 190 unvaccinated cattle with clinical signs of respiratory system infection in the provinces of Burdur, Afyonkarahisar and Isparta. For this purpose, blood samples were taken from animals with nasal and conjunctival swap samples. The samples taken were examined virologically and molecularly. The viral genome of BPIV3 RNA was investigated by RT-PCR test in 570 samples collected and the presence of antigen in 380 samples by direct immunofluorescent antibody staining method. While 2 positivity was obtained in the nasal swap samples in the molecular study, no nucleic acid was found in the conjunctival swap and leukocyte samples. In addition, antigenic structures of BPIV3 were observed in 6 nasal swap samples in the virological study. In conjunctival swap samples, the virus could not be detected. Virological diagnosis was performed in both samples in which the presence of viral genome was revealed. In addition, histopathological examinations were made in the lung tissue of an animal whose molecular and virological BPIV3 was detected. As a result of these examinations, pathological findings such as septal tissue thickening and inflammatory cell infiltrates specific to pneumonia cases were revealed. Sequence and phylogenetic analysis of a sample in which BPIV3 positivity was revealed by molecular and DIF tests were performed. As a result of these analyzes, it was concluded that the isolated strain is included in the BPIV3c genotype based on the gene region encoding the M protein.