M. Ghasemi - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.
S.M.J. Zorriehzahra - Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Tehran, Iran
J. Daghigh Roohi - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.
M. Faeed - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.
Z. Eynizadeh - Department of Animal Sciences and Marine Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.
M. Sayad Bourani - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.
S. Haghighi Karsidani - Department of fishery, Bandar Anzali Branch, Islamic Azad University, Bandar Anzali, Iran
S.F. Mirhashemi Nasab - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.
M. Asgharnia - Inland Waters Aquaculture Research center, Iranian Fisheries Science Research Institute (IFSRI), Agriculture research Education and Extension Organization (AREEO), Bandar Anzali, Iran.

Diseases are among the most critical threats to the aquaculture industry so that their prevalence leads to major economic losses. Monitoring for viral pathogens in aquaculture has high importance due to their incurability, speed of transmission, the severity of pathogenesis, and difficulties of their diagnosis. According to reports of goldfish (Carassius auratus) losses with suspected viral etiology in farms of Gilan province this study designed to inquiring about the existence of selected viral agents. Thus, the spring viremia of carp (SVC) and Koi herpesvirus (KHV) which are among the notifiable infectious diseases (OIE, ۲۰۱۹) were investigated by cell culture, PCR, RT-PCR, and immunofluorescent antibody test (IFAT). The results showed the absence of the RNA of Rhabdovirus carpio and the DNA of Koi herpesvirus in tested samples. Accordingly, ۴۷۰ bp band related to SVCV and ۲۹۲ bp band related to KHV were not confirmed in any of the samples in PCR test as well as neither Cytopathic effect in cell culture nor positive reaction in IFAT were observed. Hence, it seems that non-viral agents are the main causes of periodic population loss of goldfish in the surveyed farms and can be controlled and prevented by the health management procedures.

Goldfish (Carassius auratus), fish viruses, Koi herpesvirus (KHV), spring viremia of carp (SVC).