Abstract
Monitoring and surveillance of respiratory viral infections in different animals is essential to build up the future bovine animal health and control strategies. The aim of present study was to document the prevalence of some common bovine respiratory viral infections in different regions in Saudi Arabia. Infectious Respiratory viral diseases in cattle are an important cause of mortality especially in young calves. Out of this group of viruses, present study choses to focus on Infectious Bovine Rhinotracheitis virus (IBRV), Bovine viral diarrhea virus (BVDV), and Bovine Parainfluenza-3 virus (BPI-3V). Little is known about the prevalence of these viruses throughout the Gulf and so the primary goal of the study was to test the exposure history of different cattle herds in Saudi Arabia to the indicated viruses. To achieve this goal, 359 serum samples were collected from four different regions in Saudi Arabia (Eastern, Central, Northern, and Western regions). Commercially available ELISA kits were used to evaluate the immune response of animals against these viruses. The results showed the high seroprevalence of the indicated viruses in Saudi Arabia. The seroprevalence of IBRV, BVDV and PI-3 were 50 %, 35%, and 39% respectively. Since the animals used in the current study have not been vaccinated against the indicated viruses, it is highly likely that those herds were exposed to these viruses previously, and thus seroconverted to against these viruses. More molecular studies are urgently needed to do further characterization these viruses in Saudi Arabia. Meanwhile, application of science- based monitoring systems is highly recommended to mitigate the risk of exposure of different animals for such viruses.

Key words: IBRV, BVDV, PI-3V, ELISA, Cattle, serodiagnosis, seroconversion