CEPAVE   05420
CENTRO DE ESTUDIOS PARASITOLOGICOS Y DE VECTORES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Lesions associated with Parorchites zederi in Antartic Pygoscelids penguins
Autor/es:
MARTÍN, A.; VIDAL, V.; ORTIZ, J.; SEVA, J.; DIAZ, J. I.; JEREZ S.; BARBOSA, A.
Lugar:
Zaragoza
Reunión:
Congreso; Congreso Ibérico de Parasitología; 2011
Resumen:
The aim of this work is to describe the intestinal lesions caused by the cestode Parorchites zederi (Family Dilepididae, Order Ciclophyllidea) in three species of antarctic penguins. Twenty-five individuals (14 Pygoscelis antarctica, 9 P. papua and 2 P. adeliae) collected in DeceptionIsland (South Shetlands, Antarctic peninsula) were examined. After the necropsy, the gastrointestinal packages were extracted, and remained frozen until their later analysis at the UMU. The digestive tracts were separated by sections, opened and examined under stereoscopic microscope for tapeworms. Parasites were preserved in 70 % ethanol and morphometrically identified.  Portions of 1 cm2 of intestine with parasites in situ and/or exhibiting lesions, were removed, fixed in 10% buffered formalin, and embedded in paraffin. Later, tissues were serially sectioned (4 µm of thickness), and stained with haematoxylin and eosin according standard histological techniques. The prevalence of infection by P. zederi was 84 %. The first sections of small intestine of parasitized animals showed several oval-spherical nodules, with whitish – yellowish colour, and different sizes (from 1-2 mm up to 1,2 cm). Nodules had a well-formed smooth entrance in the mucous intestinal layer, with a grey and thickened ring-shaped orifice. One o more cestode parasites (2-15) were embedded deeply within mucosa, in the centre of the ulcerated area. In sections, these lesions were associated with marked thickening of the gut walls and necrotic-caseous content. It is necessary to emphasize the deep location of the parasites and associated lesions, extended from the mucosa to the submucosa, sparing the deepers layers (muscularis and serosa). Sometimes, a perforation of serosa could be observed, however, no evident signs of peritonitis were found. Microscopically, it was possible to confirm the muscular tropism of the parasite and a reaction to foreign body.