* Stratum corneum and the layers immediately beneath it are lost by desquamation during pro-oestrus and oestrus. This leaves low squamous epithelium, which becomes converted to columnar epithelium 1-3 weeks after the end of oestrus. | * Stratum corneum and the layers immediately beneath it are lost by desquamation during pro-oestrus and oestrus. This leaves low squamous epithelium, which becomes converted to columnar epithelium 1-3 weeks after the end of oestrus. |