Atypical parasitic lesions in slaughtered cattle in Southern Brazil / Lesões parasitárias atípicas em bovinos de abatedouro no Sul do Brasil

Abstract In this study, we described the morphological features and unusual presentations of hydatidosis, fasciolosis, and eosinophilic myositis caused by Sarcocystis species diagnosed at the slaughterhouse lines. Twenty-seven samples of atypical parasitic lesions from distinct cattle were evaluated, of which 12 corresponded to hydatidosis, 11 to fasciolosis, and 4 to eosinophilic sarcocystosis. Hydatid cysts were observed mainly in the heart, with all cases involving the left ventricle. Fasciolosis lesions involved mainly the lungs, and were characterized by a focal nodular elevated area involving the edges of the lobes. Intralesional trematodes were observed in three cases. Sarcocystosis lesions were observed in four cases, and lesions were primarily located in the skeletal and cardiac muscles. Grossly, they presented as focal or focally extensive streaks, patches, or numerous nodules that were greenish to mildly yellowish. Histologically, all the cases had intralesional ruptured cysts of Sarcocystis that were associated with severe eosinophilic myositis and myocarditis. Parasitic lesions in atypical locations and/or with aberrant responses should be promptly identified because it may mistakenly diagnosed as other potentially zoonotic diseases, such as cysticercosis and tuberculosis.

Resumo No presente estudo, são descritas as características morfológicas e as apresentações incomuns das lesões parasitárias de hidatidose, fasciolose e miosite eosinofílica por Sarcocystis spp., diagnosticadas nas linhas de abate. Foram analisadas 27 amostras de diferentes bovinos, das quais 12 correspondiam a casos de hidatidose, 11 de fasciolose e 4 de sarcocistose eosinofílica. Os cistos hidáticos foram observados predominantemente no coração, todos com localização no ventrículo esquerdo. As lesões de fasciolose envolveram principalmente os pulmões e eram caracterizadas por áreas nodulares e elevadas nos bordos dos lobos pulmonares. Trematódeos intralesionais estavam presentes em três casos. Lesões de sarcocistose foram observadas em quatro casos, com localização nos músculos esquelético e cardíaco. Macroscopicamente, observaram-se listras, manchas ou numerosos nódulos de coloração esverdeada a discretamente amarelada. Histologicamente, todos os casos apresentaram cistos intralesionais de Sarcocystis spp. rompidos e degenerados, associados à acentuada miosite e miocardite eosinofílica. A identificação das lesões parasitárias em locais poucos frequentes é de extrema importância, pois podem constituir diagnósticos diferencias de enfermidades zoonóticas, como cisticercose e tuberculose.

Gastrointestinal helminths and related histopathological lesions in black-necked swans Cygnus melancoryphus from the Carlos Anwandter Nature Sanctuary, Southern Chile / Helmintos gastrintestinais e lesões histopatológicas relacionadas em cisnes de pescoço negro Cygnus melancoryphus do Santuário da Natureza Carlos Anwandter, Sul do Chile

Abstract Black-necked swans are distributed across South America and face conservation problems in Chile according to data of the State institution SAG. The aim of this study was to identify helminths and to assess associated tissue damage via histopathology. A total of 19,291 parasites were isolated from 21 examined birds; 17 species were identified, including nematodes, flukes, and tapeworms. Of these, 12 were new host records, 13 were reported for the first time in Chile, and 5 were new records for the Neotropical region. Further, the flukes Schistosomatidae gen. sp. and Echinostoma echinatum are of zoonotic concern. Regarding histopathology, an inflammatory response was found along the birds' entire digestive tract. Nevertheless, it is difficult to declare that there is a clear association between such lesions and isolated parasites, as other noxa could be responsible as well. Although in some cases there was an evident association, such inflammatory responses and necrosis were minimal, as occurred with Capillaria, Retinometra, Catatropis, Echinostoma, and Schistosomatidae gen. sp. Nevertheless, Epomidiostomum vogelsangi caused granulomatous injuries, an important inflammatory response, and necrosis, but it always circumscribed to superficial layers of the gizzard. Conversely, Paramonostomum was not associated with an inflammatory response despite a high parasitic load.

Resumo O cisne de pescoço negro é distribuído por toda a América do Sul, e enfrenta problemas de conservação no Chile, sendo protegido pela Lei Estadual de Caça. O objetivo deste estudo foi identificar helmintos em cisnes e avaliar o dano tecidual por meio de histopatologia. Um total de 19.291 parasitas foi isolado de 21 aves examinadas, sendo 17 espécies identificadas, entre nematóides, trematódeos e tênias. Destes, 12 são novos registros de hospedeiros, 13 são reportados pela primeira vez no Chile, e 5 são novos registros para a região Neotropical. Além disso, os trematódeos Schistosomatidae gen. sp. e Echinostoma echinatum detectados têm importância zoonótica. Em relação à histopatologia, uma resposta inflamatória foi encontrada em todo o trato digestivo. Entretanto, é difícil estabelecer uma associação estrita de tais lesões com parasitas isolados, porque outros fatores também poderiam ser responsáveis. Em alguns casos, houve uma associação óbvia entre parasitas e lesões, embora a resposta inflamatória e a necrose fossem mínimas, como foi o caso dos gêneros Capillaria, Retinometra, Catatropis, Echinostoma e Schistosomatidae gen. sp. Entretanto, Epomidiostomum vogelsangi causou lesões granulomatosas com importante resposta inflamatória e necrose, mas sempre circunscrita às camadas superficiais da moela. Por outro lado, Paramonostomum não foi associado com uma resposta inflamatória óbvia apesar da alta carga parasitária.

Prevalence and histopathology of Neoechinorhynchus curemai Noronha, 1973 (Acanthocephala: Neoechinorhynchidae) in Prochilodus lineatus Valenciennes, 1836 from Volta Grande Reservoir, MG, Brazil

The present work studied the prevalence and histopathology of Neoechinorhynchus curemai Noronha, 1973 (Acanthocephala: Neoechinorhynchidae) from curimbatá, Prochilodus lineatus Valenciennes, 1836. Eighteen fishes with averages of 46.7 + 1.1 cm length and 1,674.8 + 75.6 g weight were collected with net, bimonthly from December 1995 thru December 1996 in the hydroelectric power station of Volta Grande Reservoir (Cemig), Minas Gerais, Brazil. From analysed fishes, 15 were infected with acanthocephalans in the intestine (prevalence 83.3 percent). The greatest mean intensity occurred in August 1996 with 66.5 (16 to 208) parasites. Histopathological analysis showed complete desquamation of the intestinal epithelium with severe hyperplasia and hypertrofia of the goblet cells. Severe inflammatory reaction at the submucosa, displacement of their sheaf, associated with oedema and mononuclear and eosinophilic infiltration were observed