Continuous health monitoring and disapproval of IHN (Infectious Hematopoietic Necrosis Virus) presence in rainbow trout (Oncorhynchus mykiss) broodstock by cell culture and molecular methods (RT-PCR) from 2012 to 2016 in the suburb of Yasuj (Iran)

IHNV (Infectious Hematopoietic Necrosis Virus) is one of the most important pathogens in cultured rainbow trout (Oncorhynchus mykiss). The virus causes the disease that affects the hematopoietic tissue and blood vessels of fish, especially in larvae and fingerling stages. The disease is highly contagious and causes mass fish casualty (up to 95%). Therefore, continuous health monitoring of fish farms is necessary. The objectives of the present study were to identify and track the probable presence of the virus in fish farm in Dasht-e-Rome, Kohgiluyeh and Boyer-Ahmad province, Iran. Samples were prepared from the liver, spleen, kidney, egg, sperm and larvae of the adult fish and broodfish during four years from 2012 to 2016. About one percent of the broodstock population was used for sampling (1%×3000 broodfish×4years=120fish). In order to detect the presence of IHN-virus, samples were sent to a laboratory in frozen condition. After preparation of samples, they were inoculated with two types of cell line (BF2 and EPC) and examined by the molecular methods (Reverse Transcriptase-PCR) to detect the presence of IHN virus. The results showed that all samples were free from the IHN virus and the frequency of virus was 0% in all examined samples.