Prevalence of bovine respiratory disease viruses in calves from the central desert of Iran.

Bovine respiratory disease (BRD) is a significant disease in the cattle industry worldwide. The interaction between environmental factors, hosts, livestock management, and viral and bacterial pathogens causes this disease. Viruses are crucial in the initiation and progression of BRD. This study was the first to investigate the prevalence of BRD viruses using the reverse transcription polymerase chain reaction method in nasal and eye conjunctival swabs and blood samples of 115 BRD calves in the central desert of Iran. At least one investigated virus was detected in 44 animals (38.26%). The detection rates of bovine viral diarrhea virus, bovine coronavirus, bovine adenovirus, bovine respiratory syncytial virus, bovine herpes virus-1, and bovine para influenza virus-3 were 20.00, 14.78, 5.21, 0.86, 0.00, and 0.00%, respectively. Three animals (2.60%) had a simultaneous infection with two viruses. Detection of bovine viral diarrhea virus, bovine coronavirus, and bovine adenovirus was correlated. The virus infection rates were 31.81 and 44.66% in five sampled cities. The virus detection rate in infected animals was related to the nose (26 animals; 50.09%), nose and eyes (seven animals; 15.90%), eyes (seven animals; 15.90%), nose, eyes, and blood (three animals; 6.81%), and blood (one animal; 2.27%) samples. The virus detection rate in different samples was in separate clusters. Monitoring and controlling the circulation of bovine viral diarrhea virus and bovine coronavirus in the central desert of Iran is vital due to the high detection rate. Our results highlight the necessity of investigating other viruses and bacterial agents related to the BRD in the study area.