Résumé
The only non commercial reagant necessary to process the indirect-ELISA #Trypanosoma# species is the trypanosome antigen. Production of trypanosomes for indirect-ELISA is generally made in rodents. Rare #T. vivax# strains have been adapted to rodents, and, moreover, irradiation of the rats is often necessary to produce high parasitaemia in order to prepare antigens for indirect-ELISA. Production of such antigens is a limiting factor for most of the laboratories. #T. evansi# grows easily in mice with very high spontaneous parasitaemic levels and is known to have antigenic similarities with other salivarian trypanosomes. For these reasons, the utilisation of #T. evansi# antigens in the diagnosis of #T. vivax infections could be an interesting alternative for laboratories which cannot produce #T. vivax# antigens. Qualitative studies in western blotting, and quantitative studies in indirect-ELlSA #T. vivax# and indirect-ELISA #T. evansi# have been conduced with sera from sheep experimentally infected with #T. vivax# or with #T. evansi#. The quantitative study in indirect-ELlSA with the antigens of #T. vivax# showed strong responses in homologous system (with sera from sheep infected with #T. vivax#), but low responses in heterologous system (with sera from sheep infected with #T. evansi#). On the contrary, with #T. evansi# antigens, the heterologous and homologous systems both give strong responses. It is therefore suggested that #T. evansi# antigens could be use in indirect-ELISA to detect both infections, and that positive samples to that test be tested with indirect-ELISA #T. vivax# to allow distinction of the infection by one another parasite.