Morphological and molecular identification of third‐stage Contracaecum larvae (Nematoda: Anisakidae) parasitizing Nile perch Lates niloticus in Egypt
2022
Thabit, Hasnaa | Abdallah, Ebtsam Sayed Hassan
The present study found anisakid nematodes of the genus Contracaecum occurring as third‐stage larvae in Nile perch Lates niloticus collected from the Nile River, Assiut Governorate, Egypt. The larvae were discovered either free in the abdominal cavity, stomach, or intestinal lumen, or encapsulated in a tightly coiled spiral form in the mesenteries and on the serosa of the alimentary tract. The prevalence of the parasite was 66.96%, with the larval burden ranging from 1 to 180 larvae per fish. The mean intensity and mean abundance were 27.12 and 18.16 respectively. The prevalence and intensity of infection were found to be unrelated to the weight and standard length of the fish. Light and scanning electron microscopy were used to describe the larvae, and these data were backed up by genetic data based on DNA sequencing of the nuclear ribosomal internal transcribed spacer (ITS1) and the mitochondrial cytochrome oxidase c subunit I (COI) gene, and deposited in the GenBank under the accession numbers MZ727197 and MZ753680 respectively. The phylogenetic analysis identified the isolated larvae as Contracaecum quadripapillatum.
显示更多 [+] 显示较少 [-]