A method to detect the parasitic nematodes from the family Anisakidae, in Sardina pilchardus, using specific primers of 18 S DNA gene
Résumé
Anisakiasis is the infestation of man by the third larval stage of the Anisakidae family parasites, caused by the consumption of raw or undercooked seafood. The hosts of the third larvae parasite are marine fishes, among which Sardina pilchardus is of high commercial interest in many countries. So, the detection of anisakid larvae in fisheries products (fresh and processed) is of great interest to a rapid and feasible diagnosis of parasitism. Currently, there are different types of parasite detection methods but they are all difficult and tedious. The aim of this work was to detect, using DNA-based techniques, the presence of anisakid larvae in the entire fish host. Three pairs of primers were designed in the 18 S DNA gene taking into account the maximum matching between the anisakid species sequences and the minimum matching concerning for both the fish species and some other groups of organisms that parasitize fish (non-anisakid nematodes, trematodes, and cestodes). Experimental mixtures of parasite and fish host were made and the sensitivity of anisakid DNA detection tested by PCR. All the above primers and two others combinations of them were specific for the nematode group within the studied species, and the sensitivity of detection was on the order of 1 part of nematode to 100 000 parts of fish (anisakid weight:fish sample fresh weight = 1:≈100 000).