O pinguim-de-Magalhães (Spheniscus magellanicus) migra das suas colônias reprodutivas até o extremo sul do Brasil. Esses pinguins frequentemente são acometidos por doenças, notavelmente a malária aviária, que é relatada no Brasil e no mundo. A detecção de Plasmodium spp. no esfregaço sanguíneo é o método de rotina mas apresenta baixa sensibilidade quando comparado aos métodos moleculares. Considerando o impacto negativo da malária aviária nos pinguins, o objetivo deste estudo foi detectar a presença de Plasmodium spp. em pinguins-de-Magalhães usando a Reação em Cadeia da Polimerase (PCR), verificar as alterações clínicas, hematológicas e bioquímicas e o provável prognóstico em resposta à infecção. Amostras de sangue foram obtidas de 75 pinguins para determinar o hematócrito (Ht), contagens totais de eritrócitos e leucócitos, volume globular médio (VGM), concentração de ácido úrico, proteínas totais, albumina, globulinas e atividade da aspartato aminotransferase (AST). O sangue total foi usado para ensaios de PCR. A detecção de Plasmodium spp. foi obtida em 32,0% dos indivíduos pela PCR e em 29,3% pela análise microscópica. Anorexia, diarreia e alterações neurológicas foram mais frequentes nos pinguins com malária, e uma diferença significativa no peso entre pinguins infetados e não infectados foi detectada. Ht e VGM não mostraram diferença significativa. A contagem de eritrócitos e leucócitos foi menor nos animais com a malária aviária e leucopenia esteve presente em alguns pinguins. Contagens de basófilos e linfócitos foram mais baixas nos pinguins infectados, bem como elevadas contagens de monócitos estavam presentes. Não houve diferença significativa para a atividade da AST entre os animais infectados e não infectados. Houve um aumento significativo nos valores de ácido úrico, entretanto houve redução nos valores da albumina entre os pinguins infectados avaliados. Concluiu-se que Plasmodium spp. ocorre em pinguins-de-Magalhães de centros de reabilitação no sudeste brasileiro, comprometendo o peso dos animais infectados e com alterações clínicas aparecendo em casos graves da doença. Percebeu-se que embora alterações hematológicas possam não ser conclusivas, leucopenia, monocitose e diminuição de basófilos e linfócitos revelaram prognóstico desfavorável. A infecção por Plasmodium spp. pode cursar com aumento da concentração de ácido úrico e baixos valores de albumina.

Magellanic penguins (Spheniscus magellanicus) routinely migrate from their breeding colonies to Southern Brazil often contracting diseases during this migration, notably avian malaria, which has been already reported in Brazil and throughout the world. Detection of Plasmodium spp. in blood smears is the routine diagnostic method of avian malaria, however it has a low sensitivity rate when compared to molecular methods. Considering the negative impact of avian malaria on penguins, the aim of this study was to detect the presence of Plasmodium spp. in Magellanic penguins using Polymerase Chain Reaction (PCR) and by verifying clinical, hematological, and biochemical alterations in blood samples as well as to verify the likely prognosis in response to infection. Blood samples were obtained from 75 penguins to determine packed cell volume (PCV), red blood cell (RBC) and white blood cell (WBC) counts, mean corpuscular volume (MCV), uric acid, total protein, albumin, globulin and aspartate aminotransferase (AST) activity levels. Whole blood samples were used for PCR assays. Plasmodium spp. was detected in 32.0% of the specimens using PCR and in 29.3% using microscopic analyses. Anorexia, diarrhea and neurological disorders were more frequent in penguins with malaria and a significant weight difference between infected and non-infected penguins was detected. PCV and MCV rates showed no significant difference. RBC and WBC counts were lower in animals with avian malaria and leukopenia was present in some penguins. Basophil and lymphocyte counts were lower in infected penguins along with high monocyte counts. There was no significant difference in AST activities between infected and non-infected animals. There was a significant increase in uric acid values, however a decrease in albumin values was observed in infected penguins. Based on this study, we concluded that Plasmodium spp. occurs in Magellanic penguins of rehabilitation centers in Southeastern Brazil, compromising the weight of infected animals with clinical alterations appearing in severe cases of this disease. It was also noted that, although the hematological abnormalities presented by these animals may not have been conclusive, leukopenia, monocytosis and the decrease of basophils and lymphocytes revealed an unfavorable prognosis, and Plasmodium spp. infections may progress with elevated uric acid concentration and low albumin levels.

Between 1984 and 1993 the prevalence of the Trypanosoma cruzi infection in opossums (Didelphis marsupialis) was studied in Santa Catarina and Arvoredo Islands, State of Santa Catarina, Brazil. The association of the triatomine bug Panstrongylus megistus with opossums nests and the infection rate of these triatomines by T. cruzi was also studied. Thirteen different locations were studied in Santa Catarina Island (SCI), in which 137 D. marsupialis were collected. Sixty two opossums were collected at the Arvoredo Island (AI), located 12 miles north from SCI. All captured animals were submitted to parasitological examinations that revealed the presence of T. cruzi in 21.9% of the opossums captured in SCI and 45.2% among opossums captured in the AI. The presence of P. megistus was detected in most of the D. marsupialis nests collected in the SCI, however, in the non-inhabited AI only eight triatomines were collected during the whole study. The presence of T. cruzi-infected D. marsupialis associated with P. megistus in human dwellings in the SCI, and the high infection rate of D. marsupilais by T. cruzi in the absence of a high vector density are discussed.