Study of the distribution of infectious pancreatic necrosis (IPN) in rainbow trout farms of Iran using RT-PCR

In this case-study، geographical distribution of infectious pancreatic necrosis (IPN) was studied in 18 provinces of Iran using RT-PCR during 2011-2012. Since the occurrence of coinfection by IPNV، infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicaemia virus (VHSV) with the same clinical signs can occur، all samples were tested for presence of these three virus agents. Samples of larva and juveniles from rainbow trout with clinical signs such as anorexia، exophthalmia; darkened skin and high mortality as well as sperms and oval samples were obtained. Results showed that from 214 pooled samples، 96 (44. 85%) in 15 provinces were positive for IPN. The highest relative frequency was observed in Lorestan، Isfahan، Chaharmahal va Bakhtiyari، Fars، Kermanshah، Kohgilouye va Boyerahmad، Mazandaran and Qazvin. These results show that IPN disease is distributed in north، western north، west، western south and south parts of country. Therefore it is important to improve the preventive criteria to decrease the economical losses due to the disease morbidity and mortality in farmed trout in Iran.