Helminth Communities of Owls (Strigiformes) Indicate Strong Biological and Ecological Differences from Birds of Prey (Accipitriformes and Falconiformes) in Southern Italy

We compared the helminth communities of 5 owl species from Calabria (Italy) and evaluated the effect of phylogenetic and ecological factors on community structure. Two host taxonomic scales were considered, i.e., owl species, and owls vs. birds of prey. The latter scale was dealt with by comparing the data here obtained with that of birds of prey from the same locality and with those published previously on owls and birds of prey from Galicia (Spain). A total of 19 helminth taxa were found in owls from Calabria. Statistical comparison showed only marginal differences between scops owls (Otus scops) and little owls (Athene noctua) and tawny owls (Strix aluco). It would indicate that all owl species are exposed to a common pool of 'owl generalist' helminth taxa, with quantitative differences being determined by differences in diet within a range of prey relatively narrow. In contrast, birds of prey from the same region exhibited strong differences because they feed on different and wider spectra of prey. In Calabria, owls can be separated as a whole from birds of prey with regard to the structure of their helminth communities while in Galicia helminths of owls represent a subset of those of birds of prey. This difference is related to the occurrence in Calabria, but not Galicia, of a pool of 'owl specialist' species. The wide geographical occurrence of these taxa suggest that local conditions may determine fundamental differences in the composition of local communities. Finally, in both Calabria and Galicia, helminth communities from owls were species-poor compared to those from sympatric birds of prey. However, birds of prey appear to share a greater pool of specific helmith taxa derived from cospeciation processes, and a greater potential exchange of parasites between them than with owls because of phylogenetic closeness

Meteterakis saotomensis n. sp. (Nematoda: Heterakidae) from Schistometopum thomense (Bocage) (Gymnophiona: Dermophiidae) on Sao Tome Island

Meteterakis saotomensis n. sp. is described from Schistometopum thomense (Bocage), a gymnophionan endemic to the oceanic island of Sao Tome´ in the Gulf of Guinea. The specimens were assigned to Meteterakis Karve, 1930, based on the possession of a head with three rounded lips, not set-off from the body, the absence of interlabia and cordons, females with a long vagina and males with a preanal sucker, surrounded by a cuticularised rim and caudal alae that are supported by fleshy papillae. The new species is characterised by: body length 4.2–4.5 mm (males) and 5.1–6.4 mm (females); total length of oesophagus, including pharyngeal portion and oesophageal bulb, 820–856 μm (males) and 898–1,070 μm (females); length of pharynx 57–58 μm (males) and 65–68 μm (females); spicules equal, 410–521 μm long, with tessellated ornamentation throughout their length and alae, and with bevelled tip; gubernaculum or ‘gubernacular mass’ absent; tail length 164–176 μm (males) and 214–239 μm (females), with elongated tip; vulva at 2.3–2.8mmfrom anterior end, with anterior lip forming small flap. This is the second species of Meteterakis reported from gymnophionan hosts and the first from the Afrotropical region. Selected comparative morphological data for Meteterakis spp. are presented, and data on host range and geographic distribution are updated. The name M. striaturus Oshmarin & Demshin, 1972 is corrected to M. striatura to reflect the female gender of the genus name

Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle

One of the best examples of rapid displacement of native species by an invader is the eradication of native Artemia salina and A. parthenogenetica in the Mediterranean by the introduced American A. franciscana. Previous studies based on sampling from limited time periods suggest that the success of the American species as a competitor may be due partly to different parasite burden, since native Artemia spp. have high cestode infection rates regulating their density. The aim of this study is to test the hypothesis that the helminth infection in A. franciscana in its invasive range is low throughout its annual life cycle. Samples of A. franciscana were collected every second month from La Tapa saltern (Andalusia) during one year. Five helminth species were recorded: cestodes Flamingolepis liguloides, F. flamingo, Gynandrotaenia stammeri (all flamingo parasites), Eurycestus avoceti (a shorebird parasite) and larval spirurids of the Acuariinae (the first record of nematodes in Artemia). The overall infection rate was low, with total prevalence 5.9% and prevalence of individual parasite species between 0.2 and 3.2%. The mean abundance of helminths was 0.005–0.155 (av. 0.068), 5–13 times lower than in native congeners. Waterbird counts indicate that the low infection rates cannot be explained by lack of definitive hosts. The results are consistent with the hypothesis that helminths have no regulating effect on the invasive brine shrimp in the Mediterranean. The replacement of the native populations by the invader can be partially explained by a competition mediated by parasites/predators through a differential impact on host fitnessPeer reviewe

Species diversity of dermal microfilariae of the genus Cercopithifilaria infesting dogs in the Mediterranean region

Following the recent description of microfilariae of a Cercopithifilaria sp. in a dog from Sicily, Italy, (herein after referred to as Cercopithifilaria sp. I), numerous skin samples were collected from dogs in the Mediterranean region. In addition to Cercopithifilaria sp. I (185·7±7·2 μm long), microfilariae of 2 other species were identified, namely Cercopithifilaria grassii (651·7±23·6 μm long) and a yet undescribed microfilaria, Cercopithifilaria sp. II (264·4±20·2 μm long, with evident lateral alae). The morphological differentiation among the 3 species of dermal microfilariae was confirmed by differences in cytochrome c oxidase subunit 1 and ribosomal 12S sequences examined (mean level of interspecific pairwise distance of 11·4%, and 17·7%, respectively). Phylogenetic analyses were concordant in clustering these with other sequences of Cercopithifilaria spp. to the exclusion of Dirofilaria spp., Onchocerca spp. and Acanthocheilonema spp. Dermal microfilariae collected (n=132) were morphologically identified as Cercopithifilaria sp. I (n=108, 81·8%), Cercopithifilaria sp. II (n=17, 12·9%), whereas only 7 (5·3%) were identified as C. grassii. Mixed infestations were detected in all sites examined. The great diversity of these neglected filarioids in dogs is of biological interest, considering the complex interactions occurring among hosts, ticks and Cercopithifilaria spp. in different environments

Trichosomoides nasalis (Nematoda: Trichinelloidea) in the murid host Arvicanthis niloticus: Migration to the epithelium of the nasal mucosa after intramuscular development

Knowledge of the biology of the trichinelloid subfamily Trichosomoidinae is poor. Trichosomoides nasalis is a common parasite of Arvicanthis niloticus (Muridae) in Senegal, and a procedure for experimental infections has been established. It has been demonstrated that larvae develop in striated muscle fibres, similar to Trichinella spp., but they are not arrested in the first stage, and they reach the adult stage within three weeks. In the present histological study it is shown that T. nasalis females and dwarf males migrate from the abdomen and thorax to the host’s muzzle, moving through connective tissues and between muscles. A few migrating specimens were also found in the blood vessels of the nasal mucosa. While sexes were still separated in the lamina propria of the mucosa, females recovered from the epithelium contained intra-uterine males. Worms were found between the incisors in the mucosa of the anterior and median conchae which are rich in mucous cells. Only the pseudostratified epithelium was parasitized. Under natural conditions, the inflammation of the nasal mucosa that is induced by the parasites might reduce the competitiveness of infected rodents when foraging or looking for potential mates

Trichosomoides nasalis (Nematoda : Trichinelloidea) chez le muridé hôte Arvicanthis niloticus : migration dans l'épithélium de la muqueuse nasale après le développement intramusculaire

International audienceKnowledge of the biology of the trichinelloid subfamily Trichosomoidinae is poor. Trichosomoides nasalis is a common parasite of Arvicanthis niloticus (Muridae) in Senegal, and a procedure for experimental infections has been established. It has been demonstrated that larvae develop in striated muscle fibres, similar to Trichinella spp., but they are not arrested in the first stage, and they reach the adult stage within three weeks. In the present histological study it is shown that T. nasalis females and dwarf males migrate from the abdomen and thorax to the host’s muzzle, moving through connective tissues and between muscles. A few migrating specimens were also found in the blood vessels of the nasal mucosa. While sexes were still separated in the lamina propria of the mucosa, females recovered from the epithelium contained intra-uterine males. Worms were found between the incisors in the mucosa of the anterior and median conchae which are rich in mucous cells. Only the pseudostratified epithelium was parasitized. Under natural conditions, the inflammation of the nasal mucosa that is induced by the parasites might reduce the competitiveness of infected rodents when foraging or looking for potential mates.La biologie de la sous-famille des Trichosomoidinae est peu connue. Trichosomoides nasalis est un parasite commun d’Arvicanthis niloticus (Muridae) au Sénégal, et une procédure d’infestation expérimentale a été mise au point. Il a été démontré que les larves se développent dans les muscles striés, comme pour Trichinella spp, mais elles ne s’arrêtent pas au premier stade et atteignent le stade adulte en trois semaines. Cette étude histologique montre que les femelles et des mâles nains de T. nasalis migrent depuis l’abdomen et le thorax jusqu’au museau de l’hôte, et se déplacent à travers le tissus conjonctif entre les muscles. Quelques spécimens en migration ont également été observés dans les vaisseaux sanguins de la muqueuse nasale. Si les sexes sont toujours séparés dans le lamina propria de la muqueuse, des mâles intra-utérins sont observés chez des femelles au niveau de l’épithélium. Au niveau nasal, des vers ont été trouvés entre les cornets antérieurs et médians riches en cellules muqueuses. Seul l’épithélium pseudo-stratifié est parasité. En condition naturelle, l’inflammation de la muqueuse nasale provoquée par les parasites pourrait réduire la capacité des rongeurs infectés dans leur recherche de nourriture ou de partenaire

Redescription of Onchocerca lupi (Spirurida: Onchocercidae) with histopathological observations.

BACKGROUND: Onchocerca lupi is a dog parasite of increasing zoonotic concern, with new human cases diagnosed in Turkey, Tunisia, Iran, and the United States. Information about the morphology of this nematode is scant and a detailed re-description of this species is overdue. In addition, histopathological data of potential usefulness for the identification of O. lupi infections are provided. METHODS: Male and female nematodes, collected from the connective tissue of a dog, were examined using light microscopy and scanning electron microscopy (SEM), and an histological evaluation was performed on biopsy samples from periocular tissues. RESULTS: The morphological identification was confirmed by molecular amplification and partial sequencing of cytochrome oxidase subunit 1 gene. This study provides the first comprehensive morphological and morphometric description of O. lupi from a dog based on light microscopy, SEM, molecular characterization, and histological observations. CONCLUSIONS: Data herein presented contribute to a better understanding of this little known parasitic zoonosis, whose impact on human and animal health is still underestimated. The presence of granulomatous reactions only around the female adult suggests that the release of microfilariae from the uterus might be the cause of the inflammatory reaction observed