The Experts below are selected from a list of 666 Experts worldwide ranked by ideXlab platform

G. M. Faubert - One of the best experts on this subject based on the ideXlab platform.

  • Antimicrobial action of antibodies against Giardia muris trophozoites
    Clinical and Experimental Immunology, 2008
    Co-Authors: Miodrag Belosevic, G. M. Faubert, S. Dharampaul
    Abstract:

    SUMMARY The activities of immune serum and trophozoite-specific MoAb were examined in vitro and in vivo. Immune serum and anti-Giardia muris MoAb caused immobilization of the trophozoites in vitro and were cytotoxic for trophozoites in the presence of exogenous complement. Both immune serum obtained from experimentally infected mice and anti-G. muris MoAb admmistered directly into the duodenum of mice significantly reduced the number of trophozoites in the small intestine during the acute phase of the infection. These results suggest that serum antibodies play a central role in the elimination of the primary Giardia infection.

  • oral immunization of balb c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, Peter D Lee, A Abdulwahid, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral immunization of BALB/c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral Immunization of BALB/c Mice with Giardia duodenalis Recombinant Cyst Wall Protein Inhibits Shedding of Cysts
    2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer’s patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine. Giardia duodenalis is a worldwide-distributed protozoan parasit

Miodrag Belosevic - One of the best experts on this subject based on the ideXlab platform.

  • Antimicrobial action of antibodies against Giardia muris trophozoites
    Clinical and Experimental Immunology, 2008
    Co-Authors: Miodrag Belosevic, G. M. Faubert, S. Dharampaul
    Abstract:

    SUMMARY The activities of immune serum and trophozoite-specific MoAb were examined in vitro and in vivo. Immune serum and anti-Giardia muris MoAb caused immobilization of the trophozoites in vitro and were cytotoxic for trophozoites in the presence of exogenous complement. Both immune serum obtained from experimentally infected mice and anti-G. muris MoAb admmistered directly into the duodenum of mice significantly reduced the number of trophozoites in the small intestine during the acute phase of the infection. These results suggest that serum antibodies play a central role in the elimination of the primary Giardia infection.

  • dietary lipids containing gangliosides reduce Giardia muris infection in vivo and survival of Giardia lamblia trophozoites in vitro
    Parasitology, 2004
    Co-Authors: Miodrag Belosevic, M T Clandinin
    Abstract:

    We examined whether a ganglioside supplemented diet affected the course of Giardia muris infection in mice and survival of Giardia lamblia trophozoites in vitro . Female CD-1 mice were fed 1 of 5 experimental diets: standard lab chow as a control diet; semi-synthetic diets containing 20% (w/w) triglyceride based on the fat composition of a conventional infant formula; triglyceride diet; triglyceride diet containing a low level of ganglioside (0·1% w/w); and triglyceride diet containing a high level of ganglioside (1·0% w/w of diet). After 2 weeks of feeding, mice were inoculated with G. muris by gastric intubation and fed the experimental diets during the course of the infection. Cysts released in the faeces and trophozoites present in the small intestine were enumerated at various times post-infection. The average cyst output and the number of trophozoites during the course of the infection in mice fed ganglioside-containing diet were found to be significantly lower (3-log 10 reduction) compared to animals fed control diets. The results of in vitro growth studies indicated that gangliosides may be directly toxic to the parasites. Thus, gangliosides have a protective effect against G. muris infection in vivo and affect the survival of G. lamblia trophozoites in vitro .

  • studies on the resistance reactivation of Giardia muris cysts and cryptosporidium parvum oocysts exposed to medium pressure ultraviolet radiation
    Fems Microbiology Letters, 2001
    Co-Authors: Miodrag Belosevic, Stephen A Craik, James L Stafford, Norman F Neumann, Joop Kruithof, Daniel W Smith
    Abstract:

    The ex vivo and in vivo reactivation of Giardia muris cysts and Cryptosporidium parvum oocysts after exposure to different doses of ultraviolet (UV) radiation was determined using animal infectivity. The infectivity of UV-treated parasites stored for 1–4 days (G. muris) or 1–17 days (C. parvum) at room temperature in the dark was similar to that of organisms administered immediately after UV treatment, indicating that the parasites did not reactivate ex vivo. In contrast, we observed in vivo reactivation of G. muris in three of seven independent animal infectivity experiments, when parasites were treated with relatively low doses of medium-pressure UV (<25 mJ/cm2). Our observations indicate that G. muris cysts and C. parvum oocysts exposed to medium-pressure UV doses of 60 mJ/cm2 or higher did not exhibit resistance to and/or reactivation following treatment. This suggests that when appropriate doses of UV are used, significant and permanent inactivation of these parasites may be achieved.

  • nucleic acid stains as indicators of Giardia muris viability following cyst inactivation
    International Journal for Parasitology, 1996
    Co-Authors: Ruhi Taghikilani, Lyndon L Gyurek, Gordon R Finch, Paul J Millard, Miodrag Belosevic
    Abstract:

    A reliable viability assay for Giardia is required for the development of disinfection process design criteria and pathogen monitoring by water treatment utilities. Surveys of single-staining nucleic acid dyes (stain dead parasites only), and double-staining vital dye kits from Molecular Probes (stain live and dead parasites) were conducted to assess the viability of untreated, heat-killed, and chemically inactivated Giardia muris cysts. Nucleic acid staining results were compared to those of in vitro excystation and animal infectivity. Nucleic acid stain, designated as SYTO-9, was considered the best among the single-staining dyes for its ability to stain dead cysts brightly and its relatively slow decay rate of visible light emission following DNA binding. SYTO-9 staining was correlated to animal infectivity. A Live/Dead BacLight was found to be the better of 2 double-staining viability kits tested. Logarithmic survival ratios based on SYTO-9 and Live/Dead BacLight were compared to excystation and infectivity results for G. muris cysts exposed to ozone or free chlorine. The results indicate that SYTO-9 and Live/Dead BacLight staining is stable following treatment of cysts with chemical disinfectants.

  • comparison of Giardia lamblia and Giardia muris cyst inactivation by ozone
    Applied and Environmental Microbiology, 1993
    Co-Authors: Gordon R Finch, Charles W Labatiuk, E K Black, Lyndon L Gyurek, Miodrag Belosevic
    Abstract:

    Inactivation of Giardia lamblia and Giardia muris cysts was compared by using an ozone demand-free 0.05 M phosphate buffer in bench-scale batch reactors at 22 degrees C. Ozone was added to each trial from a concentrated stock solution for contact times of 2 and 5 min. The viability of the control and treated cysts was evaluated by using the C3H/HeN mouse and Mongolian gerbil models for G. muris and G. lamblia, respectively. The resistance of G. lamblia to ozone was not significantly different from that of G. muris under the study conditions, contrary to previously reported data that suggested G. lamblia was significantly more sensitive to ozone than G. muris was. The simple Ct value for 2 log unit inactivation of G. lamblia was 2.4 times higher than the Ct value recommended by the Surface Water Treatment Rule.

Renee Larocque - One of the best experts on this subject based on the ideXlab platform.

  • oral immunization of balb c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, Peter D Lee, A Abdulwahid, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral immunization of BALB/c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral Immunization of BALB/c Mice with Giardia duodenalis Recombinant Cyst Wall Protein Inhibits Shedding of Cysts
    2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer’s patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine. Giardia duodenalis is a worldwide-distributed protozoan parasit

Kunihiko Nakagaki - One of the best experts on this subject based on the ideXlab platform.

  • oral immunization of balb c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, Peter D Lee, A Abdulwahid, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral immunization of BALB/c mice with Giardia duodenalis recombinant cyst wall protein inhibits shedding of cysts
    Infection and Immunity, 2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer's patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine.

  • Oral Immunization of BALB/c Mice with Giardia duodenalis Recombinant Cyst Wall Protein Inhibits Shedding of Cysts
    2003
    Co-Authors: Renee Larocque, Kunihiko Nakagaki, A. Abdul-wahid, P Lee, G. M. Faubert
    Abstract:

    The process of encystation is a key step in the Giardia duodenalis life cycle that allows this intestinal protozoan to survive between hosts during person-to-person, animal-to-person, waterborne, or food-borne transmission. The release of cysts from infected persons and animals is the main contributing factor to contamination of the environment. Genes coding for cyst wall proteins (CWPs), which could be used for developing a transmission-blocking vaccine, have been cloned. Since the immunogenicity of recombinant Giardia CWP is unknown, we have investigated the immunogenicity of recombinant CWP2 (rCWP2) and its efficacy in interfering with the phenomenon of encystation taking place in the small bowels of BALB/c mice vaccinated with the recombinant protein. Here we report that the immunization of BALB/c mice with rCWP2 stimulated the immune system in a manner comparable to that for a live infection with Giardia muris cysts. Fecal and serum anti-rCWP2 immunoglobulin A (IgA) antibodies were detected in the immunized mice. In addition, anti-rCWP2 IgG1 and IgG2a antibodies were detected in the serum. mRNAs coding for Th1 and Th2 types of cytokines were detected in spleen and Peyer’s patch cells from immunized mice. When the vaccinated mice were challenged with live cysts, the animals shed fewer cysts. We conclude that rCWP2 is a possible candidate antigen for the development of a transmission-blocking vaccine. Giardia duodenalis is a worldwide-distributed protozoan parasit

Ana Maria Aparecida Guaraldo - One of the best experts on this subject based on the ideXlab platform.

  • Parasite survey in mouse and rat colonies of Brazilian laboratory animal houses kept under differents sanitary barrier conditions
    Arquivo Brasileiro De Medicina Veterinaria E Zootecnia, 2000
    Co-Authors: Rovilson Gilioli, Lenira Aparecida Guaraldo De Andrade, Luiz Augusto Corrêa Passos, F.a. Silva, Daniele Masselli Rodrigues, Ana Maria Aparecida Guaraldo
    Abstract:

    A parasitological study was undertaken to determine the health status of 15 mouse and 10 rat colonies bred in 18 Brazilian laboratory animal houses maintained under different sanitary barrier conditions which supply animals for teaching, research purposes and manufacture of biological products for medical or veterinary use. Parasitological methods were used for diagnosis of mites, lices, helminthes and protozoan parasites. A questionnaire was answered by institutions with the intention to obtain information about the existence of barriers against infections and of regular sanitary monitoring program of their colonies. The questionnaire data show that the majority of the animal houses investigated do not possess an efficient sanitary barrier system able to keep animals under controlled health sanitary conditions. Ecto and endoparasite infections are widespread in the colonies and multiple infections were common in animals from most facilities investigated. The prevalences of parasites detected among the mouse and rat colonies of the laboratory animal houses investigated were: Myocoptes musculinus (46.6%), Myobia musculi (26.6%), Radfordia ensifera (13.3%), Syphacia obvelata (86.6%), Aspiculuris tetraptera (60.0%), Hymenolepis nana (53.3%), Spironucleus muris (80.0%), Tritrichomonas muris (80.0%), Giardia muris (66.0%), Entamoeba muris (20.0%), Eimeria sp. (13.3%), Hexamastix muris (26.6%), Poliplax spinulosa (30.0%), Poliplax serrata (10.0%), Radfordia ensifera (30.0%), Syphacia muris (80.0%), Hymenolepis nana (40.0%), Trichosomoides crassicauda (55.5%), Spironucleus muris (90.0%), Tritrichomonas muris (80.0%), Giardia muris (60.0%), Entamoeba muris (80.0%), Eimeria sp. (60.0%) and Hexamastix muris (60.0%).

  • Parasite survey in mouse and rat colonies of Brazilian laboratory animal houses kept under differents sanitary barrier conditions Estudo de parasitos em colônias de ratos e de camundongos em biotérios brasileiros mantidos sob diferentes condições de
    Universidade Federal de Minas Gerais, 2000
    Co-Authors: Rovilson Gilioli, Lenira Aparecida Guaraldo De Andrade, Luiz Augusto Corrêa Passos, F.a. Silva, Daniele Masselli Rodrigues, Ana Maria Aparecida Guaraldo
    Abstract:

    A parasitological study was undertaken to determine the health status of 15 mouse and 10 rat colonies bred in 18 Brazilian laboratory animal houses maintained under different sanitary barrier conditions which supply animals for teaching, research purposes and manufacture of biological products for medical or veterinary use. Parasitological methods were used for diagnosis of mites, lices, helminthes and protozoan parasites. A questionnaire was answered by institutions with the intention to obtain information about the existence of barriers against infections and of regular sanitary monitoring program of their colonies. The questionnaire data show that the majority of the animal houses investigated do not possess an efficient sanitary barrier system able to keep animals under controlled health sanitary conditions. Ecto and endoparasite infections are widespread in the colonies and multiple infections were common in animals from most facilities investigated. The prevalences of parasites detected among the mouse and rat colonies of the laboratory animal houses investigated were: Myocoptes musculinus (46.6%), Myobia musculi (26.6%), Radfordia ensifera (13.3%), Syphacia obvelata (86.6%), Aspiculuris tetraptera (60.0%), Hymenolepis nana (53.3%), Spironucleus muris (80.0%), Tritrichomonas muris (80.0%), Giardia muris (66.0%), Entamoeba muris (20.0%), Eimeria sp. (13.3%), Hexamastix muris (26.6%), Poliplax spinulosa (30.0%), Poliplax serrata (10.0%), Radfordia ensifera (30.0%), Syphacia muris (80.0%), Hymenolepis nana (40.0%), Trichosomoides crassicauda (55.5%), Spironucleus muris (90.0%), Tritrichomonas muris (80.0%), Giardia muris (60.0%), Entamoeba muris (80.0%), Eimeria sp. (60.0%) and Hexamastix muris (60.0%).Um estudo parasitológico foi realizado para verificar as condições de saúde de 15 colônias de camundongos e 10 colônias de ratos produzidos em 18 biotérios de instituições brasileiras que fornecem animais para ensino, pesquisa e produção de imunobiológicos de uso médico ou veterinário. Métodos parasitológicos foram utilizados para diagnóstico de ácaros, piolhos, helmintos e protozoários parasitos. Um questionário foi respondido pelas instituições com o intuito de obter informações sobre a existência de barreiras contra infecções e programa de fiscalização sanitária de suas colônias. Os dados do questionário mostram que a maioria dos biotérios analisados não possui um sistema de barreiras sanitárias eficiente capaz de manter animais sob condições sanitárias controladas. Infecções por ecto e endoparasitos são generalizadas nas colônias e a associação de infecções múltiplas foi comum na maioria dos animais dos biotérios analisados. A prevalência dos parasitos detectados entre as colônias de camundongos e de ratos investigadas foi: Myocoptes musculinus (46,6%), Myobia musculi (26,6%), Radfordia ensifera (13,3%), Syphacia obvelata (86,6%), Aspiculuris tetraptera (60,0%), Hymenolepis nana (53,3%), Spironucleus muris (80,0%), Tritrichomonas muris (80,0%), Giardia muris (66,0%), Entamoeba muris (20,0%), Eimeria sp. (13,3%), Hexamastix muris (26,6%), Poliplax spinulosa (30,0%), Poliplax serrata (10,0%), Radfordia ensifera (30,0%), Syphacia muris (80,0%), Hymenolepis nana (40,0%), Trichosomoides crassicauda (55,5%), Spironucleus muris (90,0%), Tritrichomonas muris (80,0%), Giardia muris (60,0%), Entamoeba muris (80,0%), Eimeria sp. (60,0%) e Hexamastix muris (60,0%)