Evaluation of environmental and management risk factors effective in the occurrence of certain viral diseases in the production center of SFP rainbow trout in the Iran

One of the most important main challenges in the production of rainbow trout trout (Oncorhynchus mykiss) in Iran is the strong dependence of production on the import of eyed eggs and losses due to the occurrence of dangerous viral diseases which, while creating dependence on foreign countries, damages billions of Tomans annually to producers. This study was done aims to monitor and evaluation of environmental and management risk factors effective in the occurrence of certain viral diseases (IPN, IHN and VHS) in the production center of Specific Pathogens Free (SPF) rainbow trout in the Iran in order to achieve management guidelines and reduction of assessed risks. For this purpose, some physical, chemical and microbial factors of SPF center's incoming water were measured twice a month for ۶ months from May to October ۲۰۱۷ based on standard methods. The results showed that the mean temperature, dissolved oxygen, pH, ammonia and total count were ۱۷±۱.۵۵°C, ۸.۳۲±۰.۶۵ mg/l, ۸.۹۸±۰.۳۷ mg/l, ۰.۰۸±۰.۰۹ mg/l and ۹۰.۵۰±۸۶.۵۸ colonies per ml, respectively. The result of the examination of the contamination of the center fish with IPN, IHN and VHS viruses was also negative. In general, the results showed that in the management of the production of SPF rainbow trout, the introduction of IPN, IHN and VHS viruses has been avoided. In general, the results showed that in the management of the production of rainbow salmon free of specific pathogens, there has been an avoidance of the introduction of IPN, IHN and VHS viruses.