Pathology of Profilicollis chasmagnathi in Olrog?s Gull from Argentina

LA SALA L; PEREZ AM; MASSONE A; MARTORELLI S; COSTAMAGNA S.

Bogotá

Congreso; XX Congreso Latinoamericano de Parasitología y XV Congreso Colombiano de Parasitología y Medicina Tropical; 2011

Federación Latinoamericana de Parasitología y Asociación Colombiana de Parasitología y Medicina Tropical

Introduction: Infestation by the acanthocephalan Profilicollis chasmagnathi have been associated with mortality in chicks of Olrog?s Gull (Larusatlanticus), a vulnerable species from the Atlantic Coast of Argentina, Uruguay and Brazil. However, there is still an important gap on the knowledge regarding pathological aspects of these infestations. Here, we present new pathological findings associated with infestations by P. chasmagnathi in Olrog?s Gull chicks. Materials and Methods: Freshly dead chicks (n = 110) of Olrog?s Gull were salvaged at a breeding colony in the Bahía Blanca estuary, Argentina. Chicks were necropsied within 4 hours of collection, and their gastrointestinal tract was fixed in 10% formalin. Infected regions were dehydrated in ethanol, embedded in paraffin, sectioned at 5 μm, stained with hematoxylin/eosin, and examined under light microscopy. Results: Areas adjacent to the parasite attachment sites had atrophic villi, mucosal sloughing, and ulcerations. Acute changes consisted of eosinophilic infiltration of the lamina propria, lymphangiectasia, hyperemia, congestion, hemorrhage, and hyperplasia and necrosis of crypts. In superficial penetrations, there was intense fibroblast proliferation, and infiltration with macrophages, lymphocytes, and eosinophils. In mild penetrations, the parasite?s proboscis was surrounded by chronic inflammatory infiltrate represented by lymphocytes, macrophages, giant cells, and eosinophils. In deep penetrations, the presoma of the worm was associated with granulomatous peritonitis, which was observable as fibrous nodules on the serosal side of the peritoneum. The space between the proboscis and the serosa was infiltrated by lymphocytes, plasma cells, macrophages, giant cells and eosinophils. Complete perforations (without granuloma formation) by immature worms were observed in chicks approximately 5 days of age. Conclusions: Our results showed advanced pathology associated with P. chasmagnathi in Olrog?s Gull chicks from very early in their post-hatching period. The presence of complete perforations by immature P. chasmagnathi in small chicks underlines the parasite?s pathogenicity in the species.