Vaginal Cytology Evaluation
Clinical Pathology
Vaginal Cytology Indications
 Examine exfoliated cells from the vagina
 Vaginal epithelium is ovarian hormonal
influenced- stages estrus for optimum breeding
time.
Knowledge of the onset of vaginal discharge
Character of the discharge
Degree of vulvar swelling
Attitude of female towards male dog
 Also useful in detecting inflammation and
neoplasia of the genital tract.
Vaginal Cytology Technique
May or may not want to use a speculum
(laryngoscope may work as well).
Carefully part labia
Direct swab craniodorsally
Swab the vaginal wall
Avoid the vestibule and clitorial fossa,
superficial cells may alter results
Roll on glass slide, let dry and stain (DiffQuik)
http://www.vetmed.lsu.edu/eilts/Multimedia
files/Sound/Video/Canine%20Cytology.mp
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Vaginal Epithelial Cell Types
Basal Cells (may not be seen)
Parabasal Cells
Intermediate Cells
Superficial Cells
Parabasal Cells
Small round cells with round nuclei and
small amount of cytoplasm
Uniform in size and shape
Intermediate Cells
May be small or large
Round nuclei, nucleus similar in size as
parabasal cells
Entire cell approximately twice the size of
parabasal cells
Cytoplasm becomes angular, irregular and
folded as cell enlarges
Superficial Cells
Largest epithelial cell
As they age and degenerate, the nuclei
becomes small, pyknotic and fades.
Cytoplasm may contain vacuoles with age
Superficial Cells Continued
Cornification is the degeneration process
Superficial cells are commonly called
cornified cells
Once nucleus is lost become Anuclear
cells
Staging the Canine Estrus Cycle
Stages of Estrus
Proestrus
Estrus
Diestrus
Anestrus
Proestrus
 Bitch has a swollen vulva, reddish vulvar
discharge
 Will not accept the male during this time
 Duration is 9 days (with possibility of 2-15)
 Parabasal cells and intermediate cells gradually
decrease in number as the cycle nears estrus
 Superficial cells appear by 2-3 day and increase
in number over time
 Erythrocytes are numerous and gradually
decline
 Neutrophils are also present and decline
Early Proestrus
Parabasal and intermediate cells
predominate
As proestrus progresses, parabasal cells
disappear as superficial cells increase.
Late Proestrus
 White Blood cells decrease in
number
 Large intermediate and
superficial cells predominate
 No parabasal cells or small
intermediate cells
 Red blood cells or present or
absent
 Bacteria is often present
Estrus
Lasts an average of 9 days
Female accepts male
Vulvar discharge is less bloody
Vulva is softer
Sometimes bloody discharge may
continue through estrus
Estrus
Superficial cells predominate (90%)
May become cornified
NO WBC’S EXCEPT AT LAST 1-2 DAYS
OF ESTRUS!!!!!!!!!!!!!!!!!!!!!!!!
Variable RBC’s
Large numbers of bacteria
Estrus-Hormonal Events
Serum progesterone increases above
anestrus range
Progesterone rise begins when LH peaks
Ovulation occurs 2 days after LH peak
Eggs take an additional 2-3 days to
mature
Fertile period is 4-7 days after LH peak
Now do blood tests to check for LH peak
Diestrus
 Abrupt decrease in superficial cells
 Increase in parabasal cells and intermediate
cells
 Many WBC’s, then decrease in late diestrus
 Variable RBC’s
 Occurs average 8 days after LH peak
 Lasts about 2 months
 Progesterone peaks 15-30 days post estrus,
then declines
Anestrus
The transition period between cycles
4-12 months
Parabasa and intermediate cells
predominate
Few WBC’s and bacteria
Feline Vaginal Cytology
 More difficult to collect
 Ovulation may be induced due to stimulation of
cervix during collection
 Similar to a dog, but develop at a faster rate.
Average estrus is 8 days, interval between
estrus period is 9 days if ovulation does not
occur.
 Usually no vaginal or scant vaginal discharge
may be seen
 Usually no RBC’s are present during proestrus
Management of Breeding
Do comparison cytology during late
proestrus and estrus
Breed every other day beginning on day 9
Use other hormonal test kits to help stage
cycle
Progesterone ELISA Assay
LH Assay