| Autor: |
Arruda IF; Toxoplasmosis and Other Protozoan Diseases, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Amendoeira MRR; Toxoplasmosis and Other Protozoan Diseases, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Bonifácio TF; Toxoplasmosis and Other Protozoan Diseases, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Raso CNDS; Toxoplasmosis and Other Protozoan Diseases, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Elidio HDSM; Center for Animal Experimentation, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Coelho JWR; Center for Animal Experimentation, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., da Silva LCCP; Center for Animal Experimentation, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil., Dos Santos IB; Center for Animal Experimentation, Oswaldo Cruz Institute, Fiocruz, Manguinhos, Rio de Janeiro 21040-900, Brazil. |
| Abstrakt: |
The highly virulent Toxoplasma gondii RH strain is maintained through successive passages in mice, but there is still a lack of studies that refine these procedures from a 3Rs perspective, where humanitarian ideals aim to minimize the stress, pain, or suffering of the animals used in the research without the loss of results. The aim of this study was to establish humane endpoints in Swiss Webster mice inoculated with the T. gondii RH strain. A total of 52 mice were infected with 5 × 10 6 tachyzoites/mL and monitored for periods of up to 5 days. The parameters body weight; hair condition; higher than normal body temperature; hypothermia; respiratory function; pain; soft stools or diarrhea; bloody diarrhea; tense, nervous, or in distress during handling; and ascites were recorded daily in score tables. The results showed that prominent piloerection, respiratory function, pain parameters, and ascites are important clinical signs to be used as a cut-off point for implementing euthanasia. The application of this refinement method helped to avoid animal suffering and pain without compromising the number of parasites recovered. We therefore suggest adopting these parameters in research protocols that require the maintenance of the T. gondii RH strain in murine models to avoid and reduce animal suffering. |
