Abstract: Through separating endometrial stromal cells (ESCs) in pyometra bitches and healthy bitches, the paper analyzed the differences of cells from the two resources, observed their growth and identified them by immunofluorescence assay. The results showed that the morphologies and characteristics of ESCs from pyometra bitches were basically consistent with the healthy ones. The former cells were stronger and grew faster. After inoculated 4 days, they integrated into the film. The majority of cells were spindle, while a few showed multiple angular. By immunofluorescence, they expressed vimentin with positive rate of 98% or more. It could be concluded that the isolated cells in the experiment were canine ESCs and the cells were not much different between mild pyometra bitches and healthy bitches.

Key words: canine; pyometra; endometrial stromal cells; immunofluorescence