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Abstract Samples obtained from 11 teleost fish species collected in waters off of the Mediterranean coasts of Sicily, Italy, were examined for the presence of Hysterothylacium spp. larvae. In total, 3,017 fish samples were examined, and the larvae recovered were used in subsequent phylogenetic studies. Fifty-eight raphidascaridid parasitic nematodes were found in the examined fish, with prevalence values ranging from 0.2% in anchovies to 60% in forkbeard samples. Twenty-seven parasites were identified as Hysterothylacium fabri and Hysterothylacium aduncum by sequencing the following regions: the nuclear ribosomal internal transcribed spacer (ITS) and the mitochondrial cytochrome c oxidase subunit II (COXII). Two other larvae collected from Lophius piscatorius had very low identity scores, with ITS and COXII sequences reported in GenBank and high genetic distances (AY603539). Pairwise comparisons between the ITS region of the H. fabri isolated from fishes from Sicilian coastal waters and those isolated from the Mediterranean Sea, Turkey (KC852206), revealed genetic differences ranging from 0.015 to 0.018. Our H. aduncum samples had very low genetic differences to H. aduncum from the Adriatic Sea (KP979763, 0.00–0.003). The concatenated phylogenetic examination of the ITS-COXII sequences by using maximum likelihood analyses indicated 3 distinct clades supported by high bootstrap values. Further molecular identification and detailed morphological analyses are needed to clarify these results and confirm the diversity and relationships within Hysterothylacium. [ABSTRACT FROM AUTHOR]

In this work a total of 949 fish samples were analysed for the identification of nematode larvae belonging to the Anisakidae family. Biomolecular application for the identification of Anisakidae larvae can be an optimal instrument for the traceability of fish products, described on the Reg. EC 178/2002. Results confirm a correlation between geographical distribution of fishes and presence of specific Anisakid larvae. FAO 37 zone (Mediterranean sea) showed a prevailing distribution of Anisakis pegreffii and a minimal presence of A. simplex s.s. in hybrid form with Anisakis pegreffii. FAO 27 zone showed a prevailing distribution of A. simplex s.s. in fish like Brosme (Brosme brosme) and infestation prevalence of Pseudoterranova krabbei and P. decipiens s.s. in Gadus morhua. Obtained results validate the hypothesis that molecular biology methods for identifying Anisakidae larvae are effective traceability markers of fish products. [ABSTRACT FROM AUTHOR]

In this study, 1029 fish and cephalopod samples came from Central-Western Mediterranean (FAO 37.1.1 and FAO 37.1.3) were analysed for Anisakidae larvae research with the aim to identify possible hybridisations between Anisakis pegreffii and Anisakis simplex s.s. species. A total of 1765 larvae were detected, with prevalence values between 8.1% and 100%. The morphologic analysis revealed characters attributable to morphotype I of Anisakis in 98.5% of the examined larvae, while 1.5% belonged to the morphotype II. PCR-based Restriction Fragment Length Polymorphism (PCR–RFLP) analysis of the entire ITS region (ITS1, 5.8S and ITS2) of nuclear ribosomal DNA (rDNA) was performed with Hinf I and Hha I restriction enzymes. The majority of the larvae examined by PCR-RFLP were identified as A. pegreffii (71%), with a prevalence on horse mackerel from FAO 37.1.3, while 10% were identified as A. simplex s.s., 2% as A. physeteris and 17% as A. pegreffii × A. simplex s.s. hybrid genotype. The sequence analysis confirmed the hybridisation in the 85% of the larvae recognised as hybrid forms by PCR- RFLP, suggesting this form as the product of natural interspecific recombination due to the presence of sympatry areas. The presence of hybrid forms were mostly found in fish samples from FAO subzone 37.1.1. This is the first report of A. pegreffii x A. simplex s.s. hybrid genotype in fishes caught off the coasts of Sicily (Southern Italy). Finally, this study provided substantial information about the geographical distribution of Anisakidae family in Central-Western Mediterranean Sea. [ABSTRACT FROM AUTHOR]

A total of 151 wild and farmed fish samples of three species ( S. aurata , D. labrax and U. cirrosa ) from south Mediterranean were examined for cadmium, lead and mercury and total lipids detection to verify possible differences between wild and farmed fish. Mercury was detected only in S. aurata samples, with mean values of 0.056 ± 0.128 mg/kg and 0.031 ± 0.033 mg/kg for farmed and wild samples, respectively. The results verified no significant differences in Pb, Cd and Hg levels between wild and farmed fish samples ( p  < 0.05). The farmed fish samples showed higher total lipids contents than wild ( p  > 0.05). As far as we know, this work report first findings on the toxic metal presence in farmed Umbrina cirrosa, showing no detectable Hg, Cd and Pb values. The results of this work seems to confirm that the presence of toxic metals could be more related to the pollution the site than the type of production.

A total of 1104 fish samples from markets of Sicily were analysed for the detection and species identification of Anisakidae nematodes. The preliminary analysis of the fish samples showed the presence of 2459 larvae. All the fish species revealed different prevalence of infestation, with a maximum of 100% for Lepidopus caudatus and a minimum of 4.5% in Sardina pilchardus. The 80% of the larvae examined by PCR-RFLP analysis belonged to Anisakis pegreffii species. The seasonal infestation trend of Anisakis was evaluated in all the fish sample examined. The results of the seasonal infestation trend showed a marked connection with the ecological aspects of the fish species examined. As far as we know, this work report for the first time important ecological aspects of Lepidopus caudatus specimens of South Mediterranean. This work could be useful to plan a seasonal fishing strategy aimed at reducing the health risks related to Anisakis .