Sanitary profile in mice and rat colonies in laboratory animal houses in Minas Gerais: I - Endo and ectoparasites / Perfil sanitário de colônias de camundongos e ratos de biotérios de Minas Gerais: I - Endo e ectoparasitos

The sanitary conditions of 13 animal houses in nine public institutions in Minas Gerais, and the presence of endo and ectoparasites of mice and rats colonies kept in these facilities were evaluated. Data about barriers to prevent the transmission of diseases and a program of sanitary monitoring were obtained through a questionnaire and local visit. Parasitological methods were performed for diagnosing mite, lice, helminthes, and protozoa parasites in 344 mice and 111 rats. Data have shown that the majority of the animal houses had neither proper physical environment nor protection barriers to prevent the transmission of infections. Parasitological results have shown that only one animal house (7.7 percent) had parasite free animals, whereas the others have presented infected animals and the prevalences of parasites in the mice colonies were: Myobia musculi (23.1 percent); Myocoptes musculinus (38.5 percent); Radfordia affinis (15.4 percent); Syphacia obvelata (92.3 percent); Aspiculuris tetraptera (23.1 percent); Hymenolepis nana (15.4 percent); Spironucleus muris (46.2 percent); Giardia muris (46.2 percent); Tritrichomonas muris (53.8 percent); Trichomonas minuta (61.5 percent); Hexamastix muris (7.7 percent); and Entamoeba muris (84.6 percent). As for the rat colonies, the prevalences were: Poliplax spinulosa (8.1 percent); Syphacia muris (46.2 percent); Trichosomoides crassicauda (28.6 percent); Spironucleus muris (85.7 percent); Tritrichomonas muris (85.7 percent); Trichomonas minuta (85.7 percent); Hexamastix muris (14.3 percent) and Entamoeba muris (85.7 percent)

Avaliaram-se as condições sanitárias de 13 biotérios de nove instituições públicas do estado de Minas Gerais, bem como a presença de endo e ectoparasitos nos camundongos e ratos criados nesses biotérios. Os dados sobre barreiras contra infecções e sobre o programa de monitoramento sanitário dos animais foram obtidos por meio de um questionário e de visitas aos biotérios. Métodos parasitológicos foram utilizados para o diagnóstico de ácaros, piolhos, helmintos e protozoários em 344 camundongos e 111 ratos. A maioria dos biotérios não possuía espaços físicos adequados nem barreiras de proteção que pudessem impedir a transmissão de infecções. Os resultados parasitológicos mostraram que em apenas um biotério não foram encontrados animais parasitados. A prevalência de parasitos encontrados em camundongos nos outros biotérios foi: Myobia musculi (23,1 por cento), Myocoptes musculinus (38,5 por cento), Radfordia affinis (15,4 por cento), Syphacia obvelata (92,3 por cento), Aspiculuris tetraptera (23,1 por cento), Hymenolepis nana (15,4 por cento), Spironucleus muris (46,2 por cento), Giardia muris (46,2 por cento), Tritrichomonas muris (53,8 por cento), Trichomonas minuta (61,5 por cento), Hexamastix muris (7,7 por cento) e Entamoeba muris (84,6 por cento). E nas colônias de ratos foram encontrados: Poliplax spinulosa (8,1 por cento), Syphacia muris (46,2 por cento), Trichosomoides crassicauda (28,6 por cento), Spironucleus muris (85,7 por cento), Tritrichomonas muris (85,7 por cento), Trichomonas minuta (85,7 por cento), Hexamastix muris (14,3 por cento) e Entamoeba muris (85,7 por cento)

Biomphalaria tenagophila/Schistosoma mansoni interaction: premises for a new approach to biological control of schistosomiasis

Biomphalaria tenagophila is very important for schistosomiasis transmission in Brazil. However its mechanisms of interaction with Schistosoma mansoni are still scantly studied. Since this snail displays strains highly susceptible or completely resistant to the parasite infection, the knowledge of that would be a useful tool to understand the mechanism of snail resistance. Particularly, the Taim strain consistently shows absolute resistance against the trematode, and this resistance is a dominant character. A multidisciplinary research group was created aiming at studying B. tenagophila/S. mansoni interaction. The possibility for applying the knowledge acquired to obtain a biological model for the control of S. mansoni transmission in endemic areas is discussed.

A Multiplex-PCR approach to identification of the Brazilian intermediate hosts of Schistosoma mansoni

Due to difficulties concerning morphological identification of planorbid snails of the genus Biomphalaria, and given a high variation of characters and in the organs with muscular tissue, we designed specific polymerase chain reaction (PCR) primers for Brazilian snail hosts of Schistosoma mansoni from available sequences of internal transcribed spacer 2 (ITS2) of the ribosomal RNA gene. From the previous sequencing of the ITS2 region, one primer was designed to anchor in the 5.8S conserved region and three other species-specific primers in the 28S region, flanking the ITS2 region. These four primers were simultaneously used in the same reaction (Multiplex-PCR), under high stringency conditions. Amplification of the ITS2 region of Biomphalaria snails produced distinct profiles (between 280 and 350 bp) for B. glabrata, B. tenagophila and B. straminea. The present study demonstrates that Multiplex-PCR of ITS2-DNAr showed to be a promising auxiliary tool for the morphological identification of Biomphalaria snails, the intermediate hosts of S. mansoni

Suscetibilidade de Biomphalaria tenagophila de Belo Horizonte e adjacencias a infeccao com tres cepas de Schistosoma mansoni. / Susceptibility of Biomphalaria tenagophila from Belo Horizonte and neighborhood to infection with 3 strains of Schistosoma mansoni

Caramujos Biomphalaria tenagophila, descendentes de exemplares coletados nos Municipios de Belo Horizonte, Sabara e Nova Lima, Estado de Minas Gerais, foram infectados experimentalmente com tres cepas de Schistosoma mansoni: "LE", de Belo Horizonte; "SS", silvestre de Sabara e "SJ", de Sao Jose dos Campos (SP). Os caramujos de Belo Horizonte foram suscetiveis as cepas "LE" (4,0%) e "SJ" (22,0%). Os moluscos de Sabara (Ravena) foram resistentes a infeccao com as tres cepas do trematodeo. Os exemplares de Nova Lima foram resistentes a cepa "LE" e suscetiveis as cepas "SS" (2,0%) e "SJ" (6,0%). Os indices de infeccao experimental foram semelhantes aos registrados por outros Autores para B.tenagophila de Minas Gerais. As cercarias da cepa "SJ", obtidas de B. tenagophila de Belo Horizonte, foram infectantes para camundongos e o numero medio e distribuicao dos vermes foram normais. Discute-se a importancia desses moluscos como hospedeiros em potencial do S. mansoni, nessa regiao