Prevalência de Cryptococcus neoformans nos pombos urbanos da cidade de Porto Alegre, Rio Grande do Sul / Prevalence of Cryptococcus neoformans in urban pigeons of Porto Alegre (RS), Brazil

Cryptococcus neoformans, levedura encapsulada, é o agente etiológico da criptococose em humanos e animais. A variedade neoformans, encontrada em fontes ambientais, incluindo fezes de pombos, é importante causa de mortalidade em indivíduos imunodeprimidos em todo o mundo. Contudo, ainda não há estudos sobre sua ecologia na cidade de Porto Alegre, onde se tem registro da ocorrência de casos humanos dessa micose. Para pesquisar fontes saprofíticas de C. neoformans na cidade de Porto Alegre, foram coletadas 88 amostras de excretas de pombos em distintas praças da cidade. Suspensões das amostras em salina estéril foram semeadas em placas com meio ágar Sabouraud e incubadas em estufa a temperaturas entre 29 e 30,5ºC. Após cinco dias, colônias mucóides foram subcultivadas para identificação através de provas morfofisiológicas. O fungo C. neoformans foi isolado em 88 (100 por cento) das amostras avaliadas, confirmando sua ocorrência nos pombos que habitam as praças da cidade.

Some bacterial pathogenies transmitted by fresh water fish to duckling

Four hundreds fish [200 Telapia nilotica and 200 Common carp] were collected from different fish farms at Sharkia province. These fish were divided into 4 equal groups. The first group was subjects to clinic and bacteriologic examination as soon as they were collected, to determine the percentage of pathogens in different fish farms. The groups 2, 3 and 4 were subjected to continuous clean water, freezing and drying then grinding respectively to detect the effect of these treatments on the incidence of the pathogens on treated fished. Eighty one day old duckling were experimentally infected by the isolated bacteria through different routes of inoculation, to determine the pathogenicity of some strains from fish to duckling. The results showed that high percentage of E. coli, Arizona, Str. foecalis, A. hydrophila, Shigella and Salmonella were appeared specially in private fish farms and San-EI-Hagar fish hatchery. The most common signs on infected fished appeared as dark black colouration emaciation and ascitis. Fifteen days duration were not sufficient to purify the fishes from the pathogenic bacteria, Str. foecalis resist freezing at- 20°C for 10 days and drying at 80 degree destroyed all the pathogenic bacterial agents. Enterobacteria, Str. faecales and A. hydrophila were highly pathogenic to duckling causing, Septicemia, emaciation and mortalities about 50, 75 and 100% respectively. Histopathologic alteration and clinical signs on infected duckling with A. hydrophila and Str. foecalis were recorded