Module 7- Vaginal Cytology

T or F, Females are born with all the ova that will be used during her lifetime

True

When do the ovaries begin functioning?

Between 8-12 months of age - at puberty

After ovulation, where are the ova transported from the ovaries?

Into the oviducts (fallopian tubes), to the respective horn of the uterus

Where does fertilization take place?

The oviducts (fallopian tubes)

Where are the fertilized ova transported to?

The uterus

What is the site of implantation and growth of fetuses?

Uterus

What are the two times that the cervix is not tightly closed to prevent a uterine infection?

During estrus and parturition

What is the cervix sealed with?

Mucus (mucous plug)

How often do dogs ovulate?

Biannual monestrus

What is the bleeding from a female dog during proestrus a result of?

Increased blood supply to the uterine wall in preparation for possible implantation

What occurs during the transition from proestrus to estrus?

Significant drop in estrogen, which reflects maturation of the follicles

Which hormone is responsible for initiating ovulation, usually occuring during early estrus?

Luteinizing hormone (LH)

Name for uses for vaginal cytology

1. Optimum time for breeding

2. Detect silent heat cycles

3. Predict a more accurate whelping date- mainly used in dogs and wildlife

4. Detect pathological diseases in the reproductive tract- VERY important

How does vaginal cytology work?

• Cells grow and slough off the vaginal wall

• Depending on which cells you are identifying, you can determine where an animal is in a cycle....vaginal cytology means tracking these changes

What species do we use VC for?

Mainly dogs and wildlife

Why doesn’t VC work for large animals?

Shorter heat cycle, come in and out within 15-20 hours

What do we use to synchronize heat cycles with large animals (ruminants) ?

Prostaglandin injections

What do we use to measure follicle size in horses?

Ultrasound

What methods are used for heat detection in large animals? (2)

1. Good record keeping

2. Herd management

3. Estrotect ( paint pouches)

4. Bull point marker or chin ball marker

5. Flehman response

What are some signs of estrus in large animals?

1. Walking more/ restless

2. animal standing to be mounted

3. flagging (tail off to the side)

4. Vulva winking

5. Calling/ vocalization

6. If offspring nursing, may get diarrhea from hormonal changes in dam

7. Decreased feed consumption

List 3 reasons why RVTS need to learn where animals are in their cycles as well as what normal vaginal cells look lile

1. More than ever for breeding wildlife

2. To help with client cost = $40/test

3. To ensure the animal is healthy before breeding

What are the 3 collection types for VC?

1. Swab

2. Labial

3. Pipette

List the steps for taking a VC swab

1. Clean the vulvar area

2. Vulvar labia are parted and everted if possible

3. Insert a premoistened cotton tipped applicator into the vagina (go dorsocranial until the advancement stops)- may use a speculum

4. Rotate the swab, remove and transfer to slide

5. Goal is to obtain sample of epithelial cells from the vagina, not the vulva

How to prepare the smear

Roll the cotton tip along the length of a glass microscope slide (2-3 tracks per slide)

List the steps of labial collection (4)

1. Clean the vulvar area

2. Massage the abdomen- trying to manipulate the cells forward

3. Vulvar labria are everted

4. Microscope slide is gently pressed against the labial mucosal area (impression smear)

When is the best/worst time to do labial collection

Best- WHen there is copious amounts of discharge

Worst- Late estrus, diestrus and estrus

Why?

Cells may be out by a day or two if you only collect from labial location

What species is commonly used for pipette VC samples?

Lab animals (rats)

How to perform Pipette VC?

1. Clean vulvar

2. Using a blunt pipette with sterile saline, introduce it the same way as the swab

3. Flush and recapture the saline a few times

4. Vaginal cells will be collected and may be placed on slide

5. Smear is done the same way as a blood film or a fresh drop with a coverslip

Define Proestrus

Before estrus

What cells will be mostly observed during proestrus?

Red blood cells

What clinical signs will be observed in proestrus?

Vulvar swelling and blood discharge

Define estrus

Peroid of time when a female is rexually receptive

What cells will be observed on VC during estrus?

Superficial cells that are largely anucleate, have angular, folded cell margins.

Define Met-estrus

Period that starts at the end of the estrus and lasts until the beginning of diestrus

(often classified together with diestrus)

Diestrus definition?

Vulva returns to normal size, female will no longer accept the male for mating.

All signs of discharge and swelling are absent, and heat is complete.

What cells characterise diestrus

• Decrease in superficial cells

• Increase in smaller intermediate cells

• Presence of neutrophils

Anestrus definition

Period of sexual rest where the reproductive system is resting

Secretions are minimal or absent

Interestrus

Period during which the female refuses to mate - period of rest

Which are the youngest cells of the vaginal epithelium/ serve as precursors of the other epithelial cell types, located along the basement membrane and rarely are seen in exfoliative cytology

Basal Cells (epithelial)

What are the smallest cells seen on slides with a round shaped cell and a nucleus, dark blue cytoplasm, 1:1 ration of nucleus to cytoplasm

Parabasal (epithelial)

• Larger than parabasal, due to the cytoplasm being larger

• Round in shape (may appear multisided)

• Nucleus about the same size as parabasal nucleus

• Cytoplasm stains less intensely then parabasal

Intermediate Cells (Epithelial)

Largest of the vaginal epithelial cells

Nucleus(if present) is small or distorted

Large amount of cytoplasm- angular borders

Cornified- karyopyknotic- means the conversion to keratin

Superficial cells (Epithelial)

Superficial cells without nuclei often seen in large sheets or strings

Metestrus cells

Contains a neutrophil in the cytoplasm

These are present just before diestrus

Foam Cells

• Have vacuoles in the cytoplasm

• May be found in prepubertal samples are should not be confused with neoplastic cells

• common in parabasal cells or TVT cells (Transmissible venereal tumor is transmitted sexually, by mucous membrane contact)

Proestrus smear, shows group of intermediate cells associated with neutrophils and red blood cells

Bacteria

Often seen on vaginal smears in huge numbers, covering cells and spilling onto the background.

Dark specks covering the superficial cells in the image are bacteria

Usually have no meanin g, part of the vaginal flora, if there are no other symptoms

The arrow is on a non-cornified superficial cell but the other cells are...?

Intermediate cells with red blood cells

Parabasal cells

Superficial epithelial cells

Non cornified

How much saline to use for rodents with the pipette method for vaginal cytology

0.25- 0.50 cc using 3 cc syringe to infuse saline then gently removed