The phase of the estrous cycle in females was determined in wet smears immediately after collection (direct cytology, unstained slides) with a Nikon microscope [20 (link),43 (link),44 (link)]. Vaginal swabs were obtained using sterile saline and examined on a slide in a drop of saline. Microscopic examination was performed with a 10× objective to determine the relationship between cell types and a 40× objective to recognize cell types.
The swabs contained four types of cells:
1. Leukocytes (neutrophils or polymorphonuclear cells), which are very small round cells.
2. Small nucleated epithelial cells, which are small non-keratinizing cells of a round or oval shape.
3. Large nucleated epithelial cells of a round or polygonal shape with serrated or angular edges.
4. Non-nuclear keratinized epithelial cells or needle-like cells.
Diestrus (the longest phase) lasted on average 48–72 h and was characterized by the predominance of leukocytes. Leukocytes were absent in the stage of proestrus and estrus. Some leukocytes and epithelial cells were detected during metestrus (6–8 h).
The swabs contained four types of cells:
1. Leukocytes (neutrophils or polymorphonuclear cells), which are very small round cells.
2. Small nucleated epithelial cells, which are small non-keratinizing cells of a round or oval shape.
3. Large nucleated epithelial cells of a round or polygonal shape with serrated or angular edges.
4. Non-nuclear keratinized epithelial cells or needle-like cells.
Diestrus (the longest phase) lasted on average 48–72 h and was characterized by the predominance of leukocytes. Leukocytes were absent in the stage of proestrus and estrus. Some leukocytes and epithelial cells were detected during metestrus (6–8 h).
Free full text: Click here
