PROFESSIONALISM
“No man ever reached to
excellence in any one art or
profession without having passed
through the slow and painful
process of study and preparation.”
-Horace
THE ESTROUS CYCLE
NORMAL ESTOUS CYCLE:
THE BITCH
Estrous Cycle: Defined as the time from the
beginning of one heat period to the beginning of
the next.
Onset of puberty: 6-24mths; Avg.: 9-10mths
The stages of the estrous cycle:
Proestrus
Estrus
Metestrus
Diestrus
Anestrus
NORMAL ESTROUS CYCLE:
PROESTRUS
PROESTRUS: the period when the bitch is
sexually attractive, but rejects the male’s
advances
Physical signs of proestrus:
Serosanguinous vaginal discharge
Vulvar swelling
Vaginal edema
Internal physical signs:
Lengthening and hyperemia of the uterine horns
Enlargement of the cervix
Thickening of the vaginal wall
PROESTRUS
Hormonal signs of proestrus:
Increasing serum concentrations of
estradiol (estrogen)
estrogen is responsible for the physical signs of
proestrus
Estrogen is being produced by the maturing
follicles in the ovary (under the influence of
Follicle Stimulating Hormone or FSH)
As proestrus progresses, the estrogen levels
begin to peak and initiate the onset of estrus.
PROESTRUS
Cytologic signs of proestrus:
Vaginal Cytology
Parabasal cells and intermediate cells
predominate; wbc’s and rbc’s present
Duration of proestrus: 3-17
days; Avg.: 9 days
VAGINAL CYTOLOGY
VAGINAL CYTOLOGY
VAGINAL CYTOLOGY
PROESTRUS
INTERMEDIATE CELLS
RED BLOOD CELLS
THE NORMAL ESTROUS CYCLE:
ESTRUS
ESTRUS: The period of acceptance
of the male
Physical signs of estrus:
The swollen vulva is less turgid
The vulvar discharge is usually less
bloody
The bitch allows mating
“standing” heat
“flagging” behavior (tail deviated to the side)
ESTRUS
Hormonal signs of estrus:
Serum estrogen peaks in late proestrus and early estrus.
The estrogen peak initiates a surge of luteinizing
hormone (LH)
LH results in ovulation (rupture) of the mature follicle
and release of the oocyte. LH also stimulates the
cells left behind in the empty follicle to multiply into
the corpus luteum (See metestrus)
serum progesterone levels begin to increase toward the
end of estrus (and beginning of metestrus)
Progesterone is produced by the corpus luteum which
is forming from the empty follicle (see metestrus)
Progesterone is the hormone that maintains
pregnancy
ESTRUS
Cytologic signs of estrus:
Vaginal cytology:
Superficial and superficial anuclear
squamous cells predominate (aka cornified
cells); rbc’s usally present, wbc’s usually
absent
Duration of estrus: 3-21 days; Avg.: 9
days
ESTRUS: VAGINAL CYTOLOGY
CORNIFIED EPITHELIAL CELLS
THE NORMAL ESTROUS CYCLE:
METESTRUS
METESTRUS: The period after
ovulation when the corpus luteum
develops.
Internal signs of metestrus:
Lining of the uterus is thick and “juicy” in
preparation for implantation of a fertilized
ovum
Loss of the cornified epithelial lining that
developed in the vagina during proestrus
and estrus
THE NORMAL ESTROUS CYCLE:
DIESTRUS
DIESTRUS: the period when the corpus luteum
has reached maximum size and effectiveness.
Begins with the bitch’s refusal to mate
Physical signs of diestrus:
None except the cessation of signs of estrus
Hormonal signs of diestrus:
Serum progesterone levels continue to increase and
peak during diestrus
In a pregnant bitches, there is a rapid pre-partum drop in
progesterone ~24 hours before partuition
In non-pregnant animals, the decline may be more gradual
DIESTRUS
Cytologic signs of diestrus:
Vaginal cytology:
A sudden decrease in the number of
superficial cells and a reappearance of
intermediate and parabasal cells, and wbc’s.
Duration of diestrus: ~2mths
Dogs and cats are unique in that their
corpora lutea appear to have
preprogrammed life spans.
DIESTRUS: VAGINAL CYTOLOGY
INTERMEDIATE CELLS
PARABASAL CELLS
DIESTRUS
PSEUDOPREGNANCY:
A prolonged diestrus
Animal may show signs of pregnancy:
Nesting behavior
Mammary enlargement
– Lactation in extreme cases
Clinical signs fade with time
THE NORMAL ESTROUS CYCLE:
ANESTRUS
ANESTRUS: Follows diestrus and ends with
the onset of proestrus; criteria vary
First time plasma progesterone reaches a level below
3 nmol/L
The moment that the influence of progesterone on the
endometrium is no longer evident.
Cytologic signs of anestrus:
Samples are almost acellular
The cells present are parabasal cells and small
intermediate cells.
Duration of anestrus: Avg.: ~4.5mths.
THE NORMAL ESTROUS CYCLE:
THE QUEEN
Onset of puberty: 6-9mths
Female cats are seasonally
polyestrous
Cycle controlled by the photoperiod and
body weight
12-14 hours of light and 2.5kgs
In the absence of ovulation or
pregnancy, repeated estrous cycles
occur every 10-14 days
THE NORMAL ESTROUS CYCLE:
PROESTRUS in the queen
PROESTRUS: The period of follicular
development, but refusal to mate
Physical signs of proestrus:
Owner may notice increased affection
No vulvar swelling or vaginal discharge in cats
Hormonal signs of proestrus:
Characterized by increasing serum estrogen
concentrations
Cytologic signs of proestrus:
Epithelial cells become cornified
Duration of proestrus: 1-2 days
THE NORMAL ESTROUS CYCLE:
ESTRUS in the queen
ESTRUS: The period of sexual receptivity
and follicle maturation
Physical signs of estrus:
Queen allows copulation
Extreme affection (head rubbing, vocalization,
crouching of the thoracic limbs with rigid
extension of the pelvic limbs, lordosis, lateral
deviation of the tail)
Hormonal signs of estrus:
Peak serum concentrations of estrogen
Cytologic signs of estrus:
Maximum vaginal epithelium cornification
Duration of estrus: 7-9 days
ESTRUS
Cats are known to be “induced ovulators”
Ovulation of the mature follicle occurs as a
result of stimulation of the vagina and cervix
during mating
FRIENDSHIP
“Friendship is like peeing on
yourself: Everyone can see it,
but only you get the warm
feeling that it brings.”
PREGNANCY AND BIRTH
VAGINITIS
Definition: an inflammatory process,
not necessarily infectious.
Prepuberal bitch (aka puppy
vaginitis)
VS.
Adult vaginitis
VAGINITIS
PUPPY VAGINITIS
Causes:
Inverted vulva
Hormonal fluctuations
Clinical signs:
Purulent vulvar discharge
+/- licking the vulva
Treatments:
systemic antibiotics
topical douching
– Signs will return when treatment is discontinued
– Condition resolves naturally after the first heat cycle
VAGINITIS
Inverted vulva
VAGINITIS
ADULT VAGINITIS
Causes:
Anatomical abnormalities
Canine herpesvirus
Clinical signs:
purulent vulvar discharge
+/- licking the vulva
peri-vulvar skin irritation or infection
Perceived urinary incontinence
VAGINAL
HYPERPLASIA/PROLAPSE
Hyperplasia/prolapse
Occurs under the influence of estrogen
Results in edematous vaginal tissue that
protrudes from the vulva
Treatment:
Ovariohysterectomy resolves the
condition permanently and is the tx of
choice
Will usually resolve spontaneously but
will recur with subsequent estrous cycles
VAGINAL
HYPERPLASIA/PROLAPSE
OTHER REPRODUCTIVE
DISORDERS:
PYOMETRA: Literally “pus in the
uterus”
High levels of progesterone cause
several changes in the uterus:
hyperplasia and hypertrophy of the
endometrial glands of the uterus
Decreased myometrial contractions
Predisoposes the uterus to bacterial
infection
– Most common bacteria isolated is E.coli
PYOMETRA
CLINICAL SIGNS:
Vulvar discharge
Vomiting
Dehydration
PU/PD
Azotemia
DIAGNOSIS:
Radiology
Ultrasound
Bloodwork
Ieukocytosis, neutrophilia with a left shift
PYOMETRA
This is a potentially life-threatening condition
PYOMETRA
An open pyometra is when the
Cervix is open and allows drainage
Of the pus
Preferred treatment is ovariohysterectomy
As well as antibiotics and fluid therapy
PYOMETRA IN A RAT
..\P10021A.jpg
C:\Users\BUNNY\AppData\Local\Microsoft\Windows\Temporary
Internet Files\Low\Content.IE5\C9I4F8D5\P10021B[1].jpg
PREGNANCY
PREGNANCY DIAGNOSIS:
Palpation (~days 25-36)
Hormone assay
Ultrasonography (~20 days)
Radiography (~day 45)
PREGNANCY: RADIOGRAPHS
PREGNANCY
GESTATION: the period of pregnancy
DOGS: 62-65
CATS: 62-65
THREE STAGES OF LABOR:
1ST:uterine contractions
2nd:delivery of the newborn
3rd:delivery of the placenta
Typically, newborns and placentas are
delivered alternately
PREGNANCY
SIGNS OF IMPENDING
PARTUITION:
Nesting behavior:12-24 hours before
Inappetance
Panting, shivering
Drop in rectal temperature ~24-48 hours
before partuition (caused by abrupt decrease
in progesterone): <100°F
PREGNANCY
LABOR, STAGE I: intermittent uterine
contractions with no sign of
abdominal straining
Restlessness, panting, nesting may
continue through stage I
Cervix dilates
PREGNANCY
LABOR, STAGE II: delivery of the newborn
Rectal temp begins to rise to normal or slightly
above
Passing of fetal fluids
Expulsive uterine contractions accompanied by
abdominal contractions
1st fetus usually delivered within 4 hours
Bitch will break the amniotic membrane, lick the
neonate intensely, and sever the umbilical cord
PREGNANCY
LABOR, STAGE II: WARNING SIGNS
The bitch should be examined by a vet for the
following reasons:
Greenish discharge, but no pup is born within 2-4 hrs
Fetal fluid passed more than 2-3 hrs previously, but
nothing more has happened
If she has had weak, irregular straining for more than
2-4 hours
If she has had strong, regular straining for more than
20-30 minutes, but no pup born
More than 2-4 hours have passed since the birth of
the last puppy and more remain
If she has been in stage II for more than 12 hours
PREGNANCY
LABOR, STAGE II
Interval between births
Usually 5-120 minutes
Partuition should never be allowed to
last more than 24 hours
PREGNANCY
LABOR, STAGE III: expulsion of the
placenta
Usually follows within 15 minutes of
each fetus
Bitch may eat the placentas, but
sometimes can be associated with
vomiting and diarrhea
Lochia – greenish postpartum discharge
of fetal fluids and placental remains will
be seen for up to 3 weeks or more
PREGNANCY COMPLICATIONS
PEOPLE
“Everyone has a photographic
memory, it’s just that some people
don’t have film.”
PREGNANCY
DYSTOCIA: Difficult birth or the inability to
expel the fetus through the birth canal
without assistance
Causes:
Abnormal fetal position or size
Uterine inertia
Narrowed birth canal
Diagnosis:
Digital palpation of vagina
Radiographs
ultrasound
PREGNANCY: DYSTOCIA
TREATMENT:
Manual manipulation: a fetus lodged in
the vaginal canal can be manually
dislodged.
For uterine inertia: oxytocin injections
result in contraction of the uterine
muscles; also, calcium preparations can
be given
C-section
PREGNANCY: INAPPROPRIATE
MATERNAL BEHAVIOR
DAM SHOULD:
Allow nursing
Grooming
Stimulate CV,RS function
Stimulates elimination and removal of waste material
retrieving
Protecting
DAM SHOULD NOT:
Attack, kill, or cannibalize her young
Be overly protective, restless, or aggressive
PREGNANCY: LACTATION
DISORDERS
Agalactia: lack of milk production
Causes include;
Stress, malnutrition, premature partuition, or infection
Galactostasis: milk stasis, which can
result in mastitis
Mastitis: a septic inflammation of the
mammary gland
Clinical signs:
Pain, discolored milk, fever, reluctance to allow
nursing, abscessed glands
PREGNANCY: LACTATION
DISORDERS
Treatment for mastitis:
Antibiotics
Warm compresses
Do not allow nursing from affected
glands
PROSTATIC DISEASES
PROSTATE: Sex gland in the dog
and cat
Located just caudal to the bladder,
encircling the proximal urethra at the
neck of the bladder
Purpose is to produce a fluid as
transport and support medium for sperm
during ejaculation
PROSTATIC DISEASE
BENIGN PROSTATIC
HYPERPLASIA
Caused by altered androgen/estrogen
ratio
Mild or no clinical signs
Tenesmus
Enlarged prostate but not painful
TX:
Castration results in a 70% decrease in
size within 14 days
BENIGN PROSTATIC
HYPERPLASIA
PROSTATITIS
Bacterial prostatitis may be acute or
chronic and it affects sexually mature dogs
Clinical signs:
Lethargy
Anorexia
Diagnosis:
Urinalysis: hematuria, increased white blood cells,
presence of bacteria
Treatment:
Antibiotics
Castration
Prostatitis can lead to abscessation
NEOPLASIA of the male genital
tract
Prostatic neoplasia is uncommon, but all
prostatic neoplasms are malignant
Transmissible venereal tumor (TVT)
Occurs only in the canine
Spreads during sexual contact
Tumors found on the penis, prepuce, and
scrotum
Cauliflower-like
Treatment:
Chemotherapy
Surgical removal of small localized masses
TVT
These tumors are friable and bleed
easily
CRYPTORCHIDISM
One or both testicles have been
retained in the abdomen or inguinal
canal
Often the retained testicle is still
functional
Dog can still produce testoterone, show
sexual desire and breed
A testicular tumor known as sertoli cell tumor
is more common in retained testicles
These animal should not be bred
CRYPTORCHIDISM
Two normal testicles
Unilateral cryptorchid
Treatment is castration – testicle
Should be removed from the
Abdomen or pushed down from
The inguinal canal
CASTRATION
http://www.lbah.com/canine/dog_neuter.html
MAMMARY TUMORS
Usually tumors of older intact females
~50% of all tumors in female dogs
3rd most common tumor in cats
Risk dramatically reduces with
ovariohysterectomy (<1% if spayed
before 1st heat)
50% of canine tumors are benign
Only 10-20% of feline tumors are benign
MAMMARY TUMORS
Malignant tumors are usually fast growing,
Invasive and ulcerated. Benign tumors are
Often small and feel like a pea.
Surgical removal is advised for all
Mammary tumors. Biopsy is required
To differentiate benign from malignant
tumors
OVARIOHYSTERECTOMY
Surgical removal of the ovaries and
uterus
http://www.lbah.com/canine/spay.html