Host biological factors and habitat influence the faunal assemblages and biodiversity worldwide, including parasite communities of vertebrate and invertebrate hosts. The ecological relationship between hosts and parasites can be mediated by interaction of host’s biological factors, as their physiological condition, diet and size, with the environmental components, somehow influencing the features of parasite infection in host populations. Here, we used boosted regression tree models to study the parasite communities of two sympatric sparid fishes, the salema Sarpa salpa and the white seabream Diplodus sargus, to investigate the role of specific host’s traits in two contiguous coastal areas along the southern-western Tyrrhenian coast of Italy characterized by different degree of deterioration. Results showed that overall and across all parasite groups (ecto-, endo- and ecto- plus endo-parasites), sampling localities were the most important predictors of abundance, species richness, and diversity for salema. Moreover, seasonality was the main predictor of endo-parasite abundance, while size-related factors explained most of the variation in species richness and diversity. In the white seabream, size-related factors and reproductive cycle-related factors were the most important predictors for the overall parasite abundance and parasite richness, respectively. Our findings suggest that the parasite community of salema and white seabream responded differently to specific biological factors, highlighting how the environmental conditions under which they live may exert a strong influence on the parasite communities of each host fish.

Background: Toxoplasmosis is a zoonotic parasitic disease caused by Toxoplasma gondii, a widespread protozoan in the phylum Apicomplexa. In Europe, several studies have demonstrated the presence of the parasite in tissues of wild boars (Sus scrofa), but no data exists on the T. gondii load in tissues which in turn may be an useful way to assess the infection risk for the consumer of wild boar meat. Methods: We sampled and tested a total of 472 tissue samples of brain, heart and masseter muscle from 177 wild boars from the Campania region of southern Italy by real-time PCR analyses for detection and quantification of T. gondii. The sensitivity and specificity of the method were calculated by ROC analysis curves. Results: PCR analysis revealed the presence of T. gondii in tissue samples of 78 out of 177 (44%) wild boars. In general, the brain presented the highest PCR prevalence (31%), followed by the heart (28.3%) and the masseter muscle (24.2%), with the highest estimated parasite numbers observed in the brain followed by the heart and masseter muscle. The PCR method showed an excellent discriminating ability for each of the examined tissues. According to the ROC analysis curves, the respective sensitivity and specificity were 99 and 100% for masseter muscle, 98 and 98% for brain and 96 and 98% for heart samples. Conclusions: The high prevalence of infection here detected suggests a widespread distribution of the parasite in the wildlife of the Campania region of southern Italy. The T. gondii burdens detected may potentially represent a source of infection for humans.

Turtle blood flukes belonging to the family Spirorchiidae (Digenea) represent a major threat for sea turtle health and are considered the most important parasitic cause of turtle stranding and mortality worldwide. Despite the large diversity of spirorchiid species found globally, there are only 2 records for free-ranging Mediterranean sea turtles that date back to the late 1800s involving just Hapalotrema mistroides Monticelli, 1896. This study describes the first fatal confirmed case of spirorchiidiasis in a free-ranging Mediterranean loggerhead turtle Caretta caretta (Linnaeus) and, owing to the complexities of taxonomic identification of these parasites, provides the first molecular characterization and phylogenetic analysis of H. mistroides from the Mediterranean Sea. The loggerhead turtle showed cachexia and digestive disorders associated with severe damage to the pancreas and intestinal ganglia, caused by deposition of Hapalotrema eggs forming granulomas. Massive Hapalotrema egg emboli in several tissues and organs and encephalitis were the most probable contributions to the death of the turtle. The congruence between the phylogenetic analysis of both the ITS2 and 28S rDNA resolved the Italian and USA H. mistroides as the same species, confirming the parasite identification. The case here described clearly indicates that the blood flukes should be considered in the differential diagnosis of Mediterranean sea turtle diseases.

Ascaridoid nematodes comprise a wide range of heteroxenous parasites infecting top fish predators and marine mammals as definitive hosts, with crustaceans, squids, and fishes acting as intermediate/paratenic hosts. Limited data exist on the species and role of several intermediate and paratenic hosts in the life cycle of these parasites. In the aim of adding knowledge on the role of squid species in their life cycle, we have here investigated the larval ascaridoid nematodes collected from the deep-sea umbrella squid Histioteuthis bonnelli and the reverse jewel squid Histioteuthis reversa captured in the Central Mediterranean Sea (Tyrrhenian Sea). Morphological study and sequence analysis of the internal transcribed spacer (ITS) regions of the ribosomal DNA (rDNA) and the mitochondrial cytochrome c oxidase subunit 2 (mtDNA cox2) gene locus revealed the occurrence of Anisakis physeteris and of an unidentified species of the genus Lappetascaris. Sequence analysis revealed that specimens of Lappetascaris from both squid species matched at 100% sequences previously deposited in GenBank from larval ascaridoids collected in octopuses of the genus Eledone of the Mediterranean Sea. The Bayesian inference tree topology obtained from the analysis of the fragments amplified showed that Lappetascaris specimens were included in a major clade comprising Hysterothylacium species collected in fishes of the families Xiphiidae and Istiophoridae. As regards the site of infection in the squid host species, A. physeteris larvae predominated (60.7%) in the gonads, while those of Lappetascaris (76.3%) were found infecting the mantle musculature. The overall high values of parasitic load suggest both squid species as transmitting hosts of third stage larvae of Lappetascaris to top predator fishes, as well as the umbrella squid as an intermediate/paratenic host in the life cycle of A. physeteris in the Mediterranean Sea.

Babesiosis is an emerging tick-borne disease caused by apicomplexan parasites with widespread geographical distribution and various wildlife species as reservoir hosts. The aims of this study were to investigate the prevalence and assess the role of free-ranging canids and mustelids in the maintenance of Babesia spp. in southern Italy. PCR analysis of splenic samples targeting the 18S rRNA gene revealed the presence of Babesia spp. in 36 of 82 (43.9%) red foxes (Vulpes vulpes) including 29 (58%) from Campania region and seven (21.8%) from Calabria region, in seven of 13 (53.8%) Eurasian badgers (Meles meles), and in one of 13 (7.7%) gray wolves (Canis lupus). Samples from other host species including 9 Eurasian otters (Lutra lutra), 1 stone marten (Martes foina), 1 least weasel (Mustela nivalis), and 1 European polecat (Mustela putorius) tested Babesia spp. negative. Sequence analysis of the 18S rRNA gene demonstrated the presence of B. vulpes in the red fox and two sequence types of badger-associated Babesia spp. in the Eurasian badger. The Babesia sp. sequence detected in the gray wolf was identical to a badger-associated Babesia sp. This study shows that the number of Babesia spp. infecting free-ranging carnivores in Italy is higher than currently believed, and suggests that these hosts may play an important role in the maintenance of the sylvatic cycle of these parasites. It is the first report of badger-associated Babesia spp. in Italy and in a gray wolf.