Research on the Virulence Identification and Preservation Methods of Desert-type Leishmania donovani Strains

ObjectiveTo determine the virulence of desert-type Leishmania donovani strains through animal infection experiments and to explore preservation methods for maintaining their pathogenicity. Methods The isolated strain was cultured in vitro for 7, 30, 36, 44, 60, 90, and 150 days, respectively， and inoculated into Lagurus lagurus (L.lagurus) with the dose of 2.6×105 per animal by intraperitoneal injection. The spleen coefficient, infection rate, and antibody positive rate of the inoculated animals were detected at day 60 after infection. The desert-type Leishmania donovani strain was further inoculated with Cricetulus migratorius (C.migratorius) and L. lagurus, respectively, for passaging and preservation. The survival time of two kinds of animals and pathogenicity change of the stain in their bodies were compared. Results After inoculation of desert-type Leishmania donovani strains cultured in vitro for 7-150 days, the spleen coefficient of inoculated L.lagurus gradually increased from 1% on day 7 to 2.2% on d