Full Length Research Paper

Use of RT-PCR in diagnosis of infectious hematopoietic necrosis in rainbow trout hatcheries, Iran

Mehdi Raissy^1,2*, Hasan Momtaz¹, Mahsa Ansari² and Manouchehr Moumeni³

¹Faculty of Veterinary Medicine, Islamic Azad University-Shahrekord Branch, Shahrekord, Iran.

²Young Researchers Club, Islamic Azad University-Shahrekord Branch, Shahrekord, Iran.

³Fishery Research Center, Islamic Azad University-Shahrekord Branch, Shahrekord, Iran.

*Corresponding author.  E-mail: mehdi.raissy@iaushk.ac.ir.

Accepted 7 June, 2010

  Abstract

Distribution of Infectious Hematopoietic Necrosis (IHN) was studied in rainbow trout fish farms in Chaharmahal and Bakhtyari Province which is a major trout culture region in Iran. Overall 150 suspected rainbow trout fry with less than 3 g body weight from 30 fish farms in Chaharmahal and Bakhtyari Province, Iran, were studied and fishes of 10 hatcheries (33.3% of all studied farms) found to be infected with IHNV. Reverse transcriptase polymerase chain reaction (RT-PCR) was applied to the detection of infectious hematopoietic necrosis virus (IHNV) using primer pairs designed for the amplification of 16S rRNA gene fragment. The product of 371 bp was amplified from the RNA extracts of infected organs of suspected fish. DNA sequencing of the PCR products demonstrated specificity of the amplification. The RT-PCR amplification of IHNV 16S rRNA gene was found to be a simple, highly specific and sensitive method allowing diagnosis of IHN in a short time.

Key words: Reverse transcription-polymerase chain reaction (RT-PCR), IHN, rainbow trout.