Abstract (EN):
The aim of this study is to identify the infective Anisakis larvae in Epinephelus aeneus and Epinephelus marginatus using morphological and molecular characterization and to examine the histopathological alterations in infected fishes. This study investigated the prevalence and mean intensity of Anisakis larvae in these two Epinephelus species sampled from the north coast of Tunisia. Third stage larvae of the nematodes Anisakis simplex sensu stricto and Anisakis pegreffii were identified by sequencing a fragment of the mtDNA cox2 gene. The phylogenetic analysis carried using the ML methods showed that sequenced species clustered together in the first Glade with representative species of Anisakis simplex sensu lato. Larvae were found infecting the stomach, intestine and body cavity of E. aeneus and E. marginatus. The prevalence of Anisakis spp. larvae (L3) reached 64.4% with mean intensity of infection 3.9 +/- 0.58 parasites.fish(-1) in E. aeneus, while in E. marginatus the prevalence was 41.5% with mean intensity of infection 3.7 +/- 0.84 parasites.fish(-1). The histological sections of infected stomach showed the presence of larvae in the submucosa and muscular layers encapsulated in a fibro-connective tissue capsule with pathological changes associated with Anisakis infection, mainly fibrosis and necrosis of infected tissues and massive mononuclear inflammatory cells surrounding the larvae.
Language:
English
Type (Professor's evaluation):
Scientific
No. of pages:
12