Abstract: In this study, selecting Mongolian sheep fetus as materials, determining the fetas sex, the results showed that they were male. The skin tissues were cultuered in vitro and the cells obtained were purified and fibroblasts were screened. Through observing, the cell modality was better in 10 generations. The spindle-shape cells showed a elongated trend with the generations increasing and the spindle-shape cells stretched obviously in 20th generation and the number of cells per unit area reduced significantly. In the meantime, the growth force of cell s declined slightly with the increasing generations by the growth curve of F5 and F10 cells. But the trend was not obvious. Through the karyotype analysis of F5 and F10 cells, we found that diploid rates were 85.71% and 76.67%, which met the reques of nuclear transfer somatic cell. Recovery of adherent cells after cryopreservation was in good conditions.

Key words: Mongolian sheep; fetus; skin; fibroblast; culture in vitro