Vaginal Smear - Estrus.
Vaginal cytology indicative of estrus. Epithelial cells are superficial, most are anuclear, and some have fading or pyknotic nuclei. Note the absence of neutrophils (almost always true in estrus) and red blood cells (sometimes true in estrus). The background here is still relatively clean, but some bacteria are seen. This is not abnormal.
Verstegen J (2009)