已知长期培养可降低利什曼原虫的感染性和毒力。Ebert等(1979)证明长期培养的前鞭毛体在仓鼠巨噬细胞内可转变为无鞭毛体,但不能重复。本文报告以Tobie氏培养基长期培养的前鞭毛体产生的某些变化。试验用仓鼠保种的杜氏利什曼原虫加以培养,每周转种一次。长期培养是在培养基内转种104次以上,短期培养转种1～4次。观察发现长期培养的前鞭毛体要比短期培养的明显为 Long-term culture is known to reduce the infectivity and virulence of Leishmania. Ebert et al. (1979) demonstrated that long-term cultured promastigotes can be converted to amastigotes in hamster macrophages but can not be duplicated. This article reports some of the changes in promastigotes that have been cultured for long periods in Tobie’s medium. The test was conducted with hamster species of Leishmania donovani cultured once a week. Long-term culture is transformable in medium more than 104 times, short-term culture transformation 1 to 4 times. Observed that the long-term cultured promastigotes than the short-term culture was significantly