ABSTRACT
Rodents used in biomedical research are maintained behind barriers to exclude microbial contaminants. Several check points have to be monitored to eliminate the potential of introducing adventitious agents into the facility. Microbiological monitoring of a mouse facility environment enables to evaluate the efficiency of sanitization and cleaning procedures, air quality, and technician good practices. At our SPF mouse facility, we implemented an environmental microbiological monitoring program based in sedimentation and swabbing, inexpensive and easy to use methods. The aim of this work was to evaluate the results and the efficiency of the monitoring program after seven years. The median for bacteria and fungi counts in the SPF sampled areas was ≤2 CFU/2 h for settle plates and <1 CFU per swabbing plate, satisfying the requirements for grade C of the EU-GMP, with some modifications. The environmental monitoring program was useful to detect early warning of problems and enabled us to define a safe range of microbiological counts. In addition, SPF status defined for our mice was maintained throughout this study, confirmed by our HM program. This work could encourage directors and technicians of other mouse facilities in Latin America and rest of the world to implement this kind of program.
Subject(s)
Animals, Laboratory/microbiology , Environmental Microbiology/standards , Environmental Monitoring/standards , Animals , Animals, Laboratory/parasitology , Animals, Laboratory/virology , Bacterial Load , Environment, Controlled , Facility Design and Construction , Female , Mice , Minute Virus of Mice , Program Evaluation/methods , Program Evaluation/standardsABSTRACT
The studies of mice susceptibility to PCV2 infection are still controversial, despite the importance of PCV2 infection in pigs. Therefore, the aim of this study is to verify the occurrence of horizontal and vertical transmission of PCV2b in mice experimentally infected. Two experiments were performed. In experiment 1 an infected male mice covered a female to verify vertical infection. The pups were tested to detected viral DNA. In experiment 2 the 21 days of age mice were inoculated with PCV2 and allocated with uninfected, i.e. contactantes, to evaluate the horizontal infection. Subsequently, the contactants and inoculated mice were tested for PCV2 DNA. The samples collected from both experiments had their DNA extracted and were further submitted to polymerase chain reaction (PCR). In experiment 1, after the gestation period, the female farrowed 10 mices of which 60% (6/10) were positive for the agent. In experiment 2, both the inoculated and the contacts animals showed no clinical changes and gross lesions of PCV2 infection, but viral DNA was recovered in four of the five animals of the contactant group. The detection of viral DNA in the offspring of the primo-infected females and in the mice that had contact with inoculated mice demonstrated that PCV2 can be transmitted vertically and horizontally.
Apesar da importância da infecção de PCV2 em suínos, os estudos de susceptibilidade de camundongos para a infecção por PCV2, ainda, são controversos. Portanto, o objetivo do presente estudo é verificar a ocorrência de transmissão horizontal e vertical de PCV2b em camundongos infectados experimentalmente. Foram realizados dois experimentos. No primeiro (experimento 1), para verificar a infecção vertical, um camundongo macho infectado cobriu uma fêmea e os filhotes foram testados. No segundo (experimento 2), para avaliar a infecção horizontal, camundongos de 21 dias de idade inoculados com PCV2 foram alocados com não infectados (caontactantes) e, posteriormente, os contactantes foram testados para PCV2. No experimento 1, após o período de gestação, a fêmea pariu 10 camundongos dos quais 60 % (6/10) foram positivos para o agente. No experimento 2, tanto animais inoculados quanto os contactantes, não apresentaram alterações clinicas e lesões macroscópicas de infecção de PCV2, mas o DNA viral foi recuperado em quatro dos cinco animais do grupo contactante. A detecção de DNA viral em filhotes de fêmeas primo-infectadas e em camundongo que tiveram contato com camundongo inoculados demonstrou que PCV2 pode ser transmitido vertical e horizontalmente. Esses resultados confirmam a importância dos roedores na manutenção e disseminação de PCV2 em granjas de suínos.
Subject(s)
Animals , Guinea Pigs , Mice , Circovirus/pathogenicity , 28573 , Circoviridae Infections/transmission , Disease Transmission, Infectious/veterinary , Animals, Laboratory/virology , DNA, Viral/analysisABSTRACT
The studies of mice susceptibility to PCV2 infection are still controversial, despite the importance of PCV2 infection in pigs. Therefore, the aim of this study is to verify the occurrence of horizontal and vertical transmission of PCV2b in mice experimentally infected. Two experiments were performed. In experiment 1 an infected male mice covered a female to verify vertical infection. The pups were tested to detected viral DNA. In experiment 2 the 21 days of age mice were inoculated with PCV2 and allocated with uninfected, i.e. contactantes, to evaluate the horizontal infection. Subsequently, the contactants and inoculated mice were tested for PCV2 DNA. The samples collected from both experiments had their DNA extracted and were further submitted to polymerase chain reaction (PCR). In experiment 1, after the gestation period, the female farrowed 10 mices of which 60% (6/10) were positive for the agent. In experiment 2, both the inoculated and the contacts animals showed no clinical changes and gross lesions of PCV2 infection, but viral DNA was recovered in four of the five animals of the contactant group. The detection of viral DNA in the offspring of the primo-infected females and in the mice that had contact with inoculated mice demonstrated that PCV2 can be transmitted vertically and horizontally.(AU)
Apesar da importância da infecção de PCV2 em suínos, os estudos de susceptibilidade de camundongos para a infecção por PCV2, ainda, são controversos. Portanto, o objetivo do presente estudo é verificar a ocorrência de transmissão horizontal e vertical de PCV2b em camundongos infectados experimentalmente. Foram realizados dois experimentos. No primeiro (experimento 1), para verificar a infecção vertical, um camundongo macho infectado cobriu uma fêmea e os filhotes foram testados. No segundo (experimento 2), para avaliar a infecção horizontal, camundongos de 21 dias de idade inoculados com PCV2 foram alocados com não infectados (caontactantes) e, posteriormente, os contactantes foram testados para PCV2. No experimento 1, após o período de gestação, a fêmea pariu 10 camundongos dos quais 60 % (6/10) foram positivos para o agente. No experimento 2, tanto animais inoculados quanto os contactantes, não apresentaram alterações clinicas e lesões macroscópicas de infecção de PCV2, mas o DNA viral foi recuperado em quatro dos cinco animais do grupo contactante. A detecção de DNA viral em filhotes de fêmeas primo-infectadas e em camundongo que tiveram contato com camundongo inoculados demonstrou que PCV2 pode ser transmitido vertical e horizontalmente. Esses resultados confirmam a importância dos roedores na manutenção e disseminação de PCV2 em granjas de suínos.(AU)