Infection and genetic detection of Hysterothylacium spp (Ascaridida: Raphidascaridinae) infesting Saurida tumbil (Bloch, 1795) and Platycephalus indicus (Linnaeus, 1758) fishes, Iraqi marine water fishes

Abstract

Hysterothylacium spp Larvae encysted within the mesenteries, peritoneum, and viscera, which is the perfect place to complete their life cycle. More than 4123 larval stages were isolated from 595 Saurida tumbil and Platycephalus indicus fish. This is a simple fact that these two species are feeding greedily. The prevalence of infection was 95.3- 100 %. Internal transcribed spacers (ITS) gene of nuclear rDNA (rDNA) were amplified by conventional PCR, using the primer sets NC5/NC2. The ITS sequences determined were compared using the algorithm BLASTn with those available in the National Center for Biotechnology Information (NCBI) database. Multiple sequence alignments (MSA) were performed by ClustalW. The result showed that there are 22 distinct taxa within the genus Hysterothylacium, followed by 4 common ancestors, with 6 clades grouped. The study showed Sequence heterogeneity in the ITS gene within Hysterothylacium spp. of nematode parasite collected from Saurida tumbil and Platycephalus indicus fish. Moreover, genetic homogeneity between the population of the Arabian Gulf and other regions seemed different through the high levels of gene flow observed somewhat in this qualitative diversity. The most important of which may be the impact of climate.

Keywords

• hysterothylacium
• anisakids
• saurida tumbil
• platycephalus indicus
• iraq