Molecular Identification of Vibrio harveyi From Larval Stage of Pacific White Shrimp (Litopenaeus vannamei) Boone (Crustacea:Decapoda)By Polymerase Chain Reaction and 16S rDNA Sequencing

Abstract

A Gram-negative, rod-shaped, motile and halophilic bacterium identified as Vibrio harveyi was isolated from hatchery-reared larval of Iran Shrimp Research Centerfollowing mass mortality . Seven isolates of Vibrio spp.were collected from nauplii of Litopenaeus vannamei and then were evaluated for characteristics including morphology, physiology and biochemistry. The results indicated that the isolates belonged to a single species that grew on Thiosulfate citrate- Bile Sucrose agar and in 1.5 to 6% NaCl, positive lysine and ornithine decarboxylation and susceptible to O/129 disk. Identification of Vibrio harveyi strainIS01 (1 of 7 isolates) was confirmed by Polymerase Chain Reaction assay for Vibrio harveyi (expected amplicon 1493 bp). The 16S ribosomal DNA sequence (National Center for Biotechnology Information, GenBank accession number GU974342.1) gave 99% sequence identity to V. harveyi ATCC: 35084 (GenBank accession number EU130475.1).