312 ESVP/ECVP Proceedings 2009 141:4, 2009

137MORPHOLOGICAL CHARACTERISTICS OF ALVEOLAR

ECHINOCOCCOSIS IN DOGSA.Th.A. Weiss*, C. Bauer y and K. Kohlerz

*Department of Veterinary Pathology, Freie Universitat Berlin, Berlin,yInstitute of Parasitology, Justus-Liebig-Universitat Giessen, Giessen and

zInstitute of Veterinary Pathology, Justus-Liebig-Universitat Giessen, Giessen,Germany

Introduction: Echinococcus multilocularis is a tapeworm with zoonoticpotential and is common in the northern hemisphere. Naturally, foxesand other canids are its definitive hosts and rodents act as intermedi-ate hosts. Additionally, many other mammalian species, includingdogs and man, can be infected as intermediate hosts. In the interme-diate host the liver is most often affected with cystic and infiltrative,tumour-like lesions.Materials and Methods: Lesions in 10 dogs with naturallyacquired alveolar echinococcosis were characterized using morpho-logical and immunohistochemical methods.Results: Metacestode tissue was surrounded by prominent, fibrousconnective tissue intermixed with inflammatory cells consisting ofvarying numbers of epithelioid macrophages, Langhans’- and foreignbody-type giant cells, T lymphocytes, B lymphocytes and plasmacells, as well as neutrophils and/or eosinophils. Many of the metacest-odes contained no protoscolices and thus were sterile.Conclusions: Alveolar echinococcosis is an emerging differentialdiagnosis for proliferative lesions of the liver. Similar to the situationin man, a high proportion of metacestodes in dogs are sterile.

139HISTOLOGICAL EVALUATION OF EFFECT OF INVASIVE

AND SEMI-INVASIVE METHODS OFELECTROSTIMULATION ON THE HEALING PROCESS IN

THE RABBIT FEMURP. W1aszczuk*, G. Bierzynska-Macyszyn*, J. Wolanska-

Karut*, Z. Dobrosz*, T. Bielecki y, Z. Gajda z, J. Szewczenko x,J. Stojko{ and T. Ga�zdziky

*Department of Pathomorphology, SUM, Katowice, yDepartment and Clinic ofOrthopaedics, SUM, Sosnowiec, zOrthopaedics Ward, Municipal Hospital,Siemianowice, xInstitute of Engineering and Biomedical Materials, SilesianTechnical University, Gliwice and {Department of Bioanalysis, Sanitary

Sciences and Environmental Studies, Faculty of Pharmacy, SUM, Sosnowiec,Poland

Introduction: Semiconduction and piezoelectricity are importantproperties of bone. Current passing through callus enhances transportof mineral substances, thus stimulating regeneration of bone structureand function. Against this background, electrostimulation of boneunion is investigated.Materials and Methods: The aim of this study was to evaluate theimpact of invasive and semi-invasive electrostimulation with directand alternating currents on the development of synosthosis in thefemur of rabbits. The most recent stimulators and metallic implants,with passive-diamond layers developed by IMIiB of Politechnika�Slaska, were used. Routine histological examinations were enhancedby non-demineralized processing methods. Immunohistochemistrywas assessed using a computer system measuring cumulative opticaldensity.Results: A range of values of electrical stimulation accelerated syn-osthosis in rabbits, influencing both the number and activity of cellsinvolved in this process.Conclusions: The results provide encouragement for further studieson electrostimulation in clinical practice as a supportive method forsynosthosis.

138PCV2-ASSOCIATED MYOCARDITIS WITH NECROSIS IN

A FEEDER PIGD. Wiederkehr*, H. Weibel y and X. Sidlery

*Institute of Veterinary Pathology, University of Zurich and yDepartment ofFarm Animals, University of Zurich, Switzerland

Introduction: Porcine circovirus type 2 (PCV2) is associated witha variety of disease syndromes in pigs, including post-weaning multi-systemic and wasting syndrome (PMWS). Microscopical lesions inPMWS include depletion and histiocytic infiltration of lymphoid tis-sue. PMWS usually occurs in pigs at 7 e 12 weeks of age. Cardiovas-cular lesions associated with PCV2 are reported in mummified andstillborn piglets and in piglets 4 e 7 weeks of age without typicalPMWS lesions.Materials and Methods: A feeder pig, 20 weeks of age, was inves-tigated grossly and by histology and immunohistochemistry forPCV2.Results: Clinical signs were wasting, dyspnoea and cardiac insuffi-ciency. Hydrothorax and dilation of the right atrium were visibleon gross examination. Microscopical studies showed interstitial ne-phritis, bronchointerstitial pneumonia and severe depletion and ne-crosis of lymphoid tissues with large quantities of PCV2 antigen.Mild lymphoplasmacytic infiltrates and multifocal necrosis were pres-ent in the myocardium. PCV2 antigen was present in the necroticareas and in macrophages and endothelial cells in the heart vessels.Conclusions: Myocarditis and myocardial necrosis in a feeder pigseverely infected with PCV2 is a unique finding. The occurrence ofPCV2 antigen in endothelial cells and associated leucocytes is sugges-tive of an underlying vasculitis in the course of PMWS.

140A PERIPHERAL PRIMITIVE NEUROECTODERMAL

TUMOUR IN A DOGO. Yadegar*, S. Hesaraki* and G.A. Chamheidariy

*Faculty of Specialized Veterinary Sciences and yIslamic Azad University,Science and Research Branch, Iran

Introduction: Neuroectodermal tumours are rarely reported inman and animals. This report describes an 8-year-old male Ger-man shepherd dog, which was referred to the veterinary clinic ofTehran Azad University.Materials and Methods: Following surgery, representative samplesof lesions were fixed in 10% neutral buffered formalin. After decalci-fication and paraffin wax embedding, sections were prepared andstained with haematoxylin and eosin.Results: Clinical evaluation showed a pedunculated ulcerativemass 8� 5 � 6 cm in the mandible. Radiographically, the masswas associated with lysis of the surrounding bone and there wasno evidence of metastases to other organs. Histologically, themass was composed of broad sheets of uniformly small, round tooval cells with thin rims of basophilic cytoplasm, pale chromatinand indistinct nucleoli. The tumour cells labelled positively forS100, neuron specific enolase (NSE) and glial fibrillary acidic pro-tien (GFAP), and negatively for synaptophysin.Conclusions: The positive reaction for NSE and S100 showed thatthe tumour did not originate from haemopoietic stem cells or muscleand the positive reaction for GFAP indicated a nervous system origin.Immunohistochemical methods are indispensable in the differentialdiagnosis of neuroectodermal tumours.