The study on probable of the viral haemorrhagic septicaemia (VHS) in some rainbow trout propagation and breeding by histopathology and molecular techniques in Iran

To investigate of the contamination of rainbow trout propagation and breeding centers in Iran to viral haemorrhagic septicemia (VHS tissue samples from liver, kidney, spleen, bronchia, heart, intestine, and pancreas of affected rainbow trout were taken and prepared for both molecular and pathological techniques. Comparison of results showed 15 out of 100 examined samples with thepathology method and 10 out of 100 examined samples with the PCR are positive and the remains are negative with no pathognomonic signs. The obtained results shows that some rainbow trout hatcheries are contaminated in different regions of country, therefore, a definition of prevention, control program and eradication criteria is essential to protect the unaffected areas in the country. Theresults of this study revealed the high morbidity of VHS virus in some centers of rainbow trout propagation and breeding in the country. In concluding two diagnostic methods, of this study are very useful for virus isolation and it is reported for the first time in Iran.