Somatic and meiotic chromosomes in male and female of Pomphorhynchus laevis Muller, 1776 (Acanthocephala: Pomphorhynchidae).

A detailed cytological description of somatic cell divisions, spermatogenesis, and the prophase stages of primary oocytes of Pomphorhynchus laevis Muller is reporte

Cutaneous myxidiosis in European eel, Anguilla anguilla (Linnaeus, 1758): Histopathology, histochemistry and laminin immunohistochemistry

Histopathology, histochemistry and immunohistochemistry of the integument of European eel, Anguilla anguilla (Linnaeus, 1758), infected by Myxidium sp. are reported. Skin samples from affected and unaffected eels were dissected, formalin fixed, paraffin embedded, sectioned and stained with H&E, Periodic acid–Schiff's staining method, Alcian Blue 8 GX pH 2.5/Periodic acid–Schiff's and McCallum-Goodpasture's Gram stain. Moreover, immunohistochemistry was performed using a primary polyclonal laminin antibody. Histologically, cysts (diameter 2–3 mm) were observed mainly under the scale pockets, encircled by a thin collagen layer, lined by elongated, flattened fibroblasts and containing bipolar, PAS- and Gram-positive spores with opposite polar capsules. The epidermis stretched by the underlying cyst appeared dysplastic, thinned with a significant reduction in mucous cells number. Only inconsistent and aspecific inflammatory reaction was noted around the cysts at the dermis/epidermis interface. Intense laminin-like protein immunolabel was documented in the plasmodial ectoplasm and related to host anergia. This was the first report of laminin immunolabel in a member of the Myxozoa. Epidermal dysplasia represents likely an aspecific response against the underlying tensile force exerted by the developing parasite cyst, while fibroblast and collagen encapsulation denote a parasite-driven host response protecting, rather than harming, the encircled parasite

The chromosome complement of Leptorhyncoides plagicephalus (Westrumb, 1821), (Acanthocephala: Rhadinorhynchidae).

The study of mitotic and meiotic chromosomes of Leptorhyncoides plagicephalus is reported

Indagine parassitologica su Acipenser naccarii (Osteichtyes, Acipenseriformes) del fiume Po infestato da Leptorhynchoides plagicephalus (Acanthocephala).

Eighteen Acipenser naccarii specimcns, out of 22 cxamined (82%) from the Po rivcr proved to be infected by Leptorhynchoides plagicephalus. The parasite causes extensive lesions to the intestinal mucosa. As a response to parasitic presence in the attachment zone, the host tissue produces a fibrous thickening and shows a markcd infiltralion of leococytcs, mainly Lymphocytes and eosinophilic granulocytes. The prevalence of infection was found to increase with sturgeon age and there was no relationship with host sex

Histopathology in Atherina boyeri (Pisces: Atherinidae) resulting from infection by Telosentis exiguus (Acanthocephala).

The hystopatology developing in the sand smelt Atherina boyeri Risso 1810 from Northern Italy as the result of a natural infection by Telosentis exiguus Von Linstow 1901 (Achanthocephala) was studied and desribed. Microscope examination of sections of intestinal tissue showed that the parasites did not penetrate through all intestinal layer, and that damage was mostly limited to the epitheliu

Osservazioni istologiche sul tratto digerente di Acipenser naccarii (Bonaparte) del fiume Po infestato da Leptorhyncoides plagicephalus (Acanthocephala).

Information is provided regarding thè attachment mechanism and damage Leptorhynchoides plagicephalus (Acanthoce-phala) causes to digestive tract of Acipenser naccarii. Seventeen out of twenty-one A. naccavii specimens examined proved to be infected by L. plagicephalus. The parasite attaches itself to thè depth of intestinal folds by means of its pro-boscis causing extensive lesions which can become thè site of secondary infec-tions brought about by pathogenic microorganisms such as bacteria. The L. plagicephalus proboscis rarely passes beyond thè compact layer of lamina propria ; although it occasionally reaches thè circular muscle layer of intestinal wall. As a response to parasitic presence in thè attachment zone, thè host tissue produces a fibrous thickening and shows a marked infiltration of leucocytes, mainly lymphocytes and eosinophilic granulocytes