Molecular identification and phylogenetic analysis of Vibrio harveyi strains isolated from Pacific white shrimp (Litopenaeus vannamei Boone, 1931) in Tiab region, Hormozgan province

In this research Vibrio harveyi strains were isolated and identified from hepatopancreas of Litopenaeus vannamei from Tiab region, Hormozgan province. Shrimps samples were collected from five different ponds in northern and southern Tiab shrimp culture sites. Isolation phase was performed by dilution and inoculation of hepatopancreas samples on thiosulfate citrate bile salts sucrose agar medium. Purified isolates were identified phenotypically based on morphological, biochemical and physiological methods. Genomic DNA of five selected Vibrio harveyi strains were extracted and their 16S rRNA genes were amplified. Comparison of amplified 1000 bp sequence of 16srRNA genes with registered sequences in NCBI gene bank by megablast software exhibited high homology between isolated strains and Vibrio harveyi ATCC BAA-1116. Phylogenetic analysis by MEGA 6 sofware based on neighbour Joining method showed that isolated strains had similar monophyletic origin. According to these results presence of V. harveyi strains in hepatopancreas of Litopenaeus vannamei from Tiab region were genetically confirmed.