Abnormalities and infertility in female small animals.

• What is the common age of puberty in bitches?

  6-24 months.

  smaller breeds tend to go through puberty earlier than large breed dogs.
• What is the normal oestrus cycle length in bitches?

  Normal proestrus and oestrus is 20 days.

  Normal luteal phase is 65 days.

  Normal anoestrus is 150 days

  Total cycle is about 7 months.
• What would indicate that a cycle had been missed in the bitch?

  Progesterone will be elevated for 70 days.

  There may be mammary gland enlargement.

  There may be lactation

  There may be behavioural typical pseudopregnancy.

  All of these are possibilities but measurement of progesterone is the most reliable, which is measured with a blood test.
• Based on basic principles what are most likely to result in a failure of the onset of puberty

  There is a systemic disease (bitch ill and underweight for other reasons).

  Exogenous reproductive steroids have been given (e.g. a performance animal).

  There is a chromosonal abnormality.

  The ovaries are abnormal

  There is hypothalamic or pituitary disease (rare)

  There are no ovaries (very rare).
• What is primary anoestrus in the bitch?

  The bitch has never cycled.

  Delayed puberty
• How do you diagnose primary anoestrus in the bitch?

  On presentation collect relevant history (age, exogenous steroid use).

  Clinical exam for signs systemic disease.

  Clinical exam or signs of masculinisation (clitoral enlargement).

  Consider tests to see if cycle has been mossed (progesterone or clinical exam).
• How do you treat primary anoestrus in the bitch?

  At 24 months consider attempting oestrus induction using cabergoline (Galastop) - a response will tell you if there is ovarian tissue.
• Secondary anoestrus in the bitch

  Bitch has passed through puberty then fails to return to oestrus at expected interval.

  Commonly associated with failure of observation.

  • Detected as for delayed puberty.

  May be normal for Basenji to cycle every 12 month

  Occasionally related to:

  • Systemic disease
  • Drug-induced (corticosteroids, progesterone).

  If clinically well and > 12 months since last oestrus consider oestrus-induction (e.g. with Cabergoline).
• Primary anoestrus in the queen

  Puberty doesn’t occur as expected.

  First oestrus between 6 to 10 months of age.

  • But influenced by season of birth.
  • And body weight/ condition score.
  • Puberty frequently occurs during the spring.

  If no oestrus behaviour after age 10 months and it is spring.
• Secondary anoestrus in the queen

  Most commonly associated with inadequate lighting regimes in cattery housed queens (14 hour light abolishes anoestrus).

  May also occur as seen in the bitch with systemic disease or drug-induced suppression (corticosteroids, progesterone).
• Overview of abnormal cycles

  Abnormal cycles are especially common at the first oestrus.

  They are often associated with either inadequate LH release or too few LH receptors.

  A common feature therefore is failure of ovulation.
• If there is ovulation failure which of the two following outcomes might occur?

  1. Signs of oestrus would stop abruptly.
  2. Oestrus signs might persist as follicles wane away slowly.
  3. There will be no return to oestrus
  4. There will be a more rapid return to oestrus as there is not luteal phase.

  2,4
• Failure to ovulate in the queen

  Remember queen is an induced ovulator.

  Each copulation causes a release of LH but:

  • <50% of queens ovulate following a single mating.
  • >90% of queens ovulate if mated 3 times at 4 hour intervals.

  Thus ensure that multiple matings occur on day 2 or 3 of oestrus.

  Or consider induction of ovulation with a single injection of 500 IU/cat hCG on day 1 of oestrus.

  Queens that don’t ovulate return to oestrus after 2-3 weeks whereas those which ovulate have a 45 day luteal phase.
• Causes of signs of persistent oestrus

  Failure to ovulate (pubertal animal).

  Follicular cysts (rare in the bitch).

  Follicular neoplasia (rare in the bitch).

  Adrenal neoplasia (rare in the bitch).
• Bursal cysts

  It is very common to find cyst like structures at spay.

  These are usually para-bursal in origin and are not significant for cyclicity or fertility.

  Cystic structures in the broad ligament, ovarian bursa are very common. This would have been normal oestrus as can be longer than 21 days, so could end up spaying a dog that doesn’t need to be spayed.
• What are the common causes of exogenous oestrogen exposure?

  Often exposure to HRT creams or patches.

  Common in younger (smaller) dogs.

  Sometimes seen in smaller neutered animals.
• True ovarian cysts in the Bitch.

  True follicular and luteal cysts are rare:

  • Follicular cysts produce oestrogen
  • Thus signs of persistent oestrus.
  • Luteal cysts produce progesterone
  • Thus signs of acyclicity and occasionally pyometra
• Functional ovarian cysts

  Follicle cysts:

  • May respond to hCG administration (ovulate and dog goes into luteal phase)
  • Or may need suppression with progestogens.

  Luteal cysts

  • Usually only diagnosed when OVH because of pyometra. No treatment reported.
• Ovarian tumours

  Very rare.

  Most frequent is granulosa cell tumour.

  Often endocrinologically inactive:

  • If produce oestrogen:
  • Persistent oestrus and bone marrow suppression
  • If produce progesterone
  • Failure to cycle
  • Occasionally pyometra

  Ultrasound of radiographic diagnosis.

  Do not commonly metastasise.

  Treatment is OVH

  Can spread by trans-coelomic seeding therefore care when remove ovaries.
• What is the anatomical site of the fusion of the Mullerian Ducts with the Urogenital sinus?

  Vagina/ vestibule
• Pain at coitus - Vestibulo-vaginal remnants

  Remnant tissue at the junction between the vestibule and the vagina. May be:

  • Circumferential narrowing
  • Sagittal bands.

  Occasionally at junction vulva and vagina.

  Clinical signs:

  • Pain at attempted coitus
  • Chronic vaginitis in some cases.

  Treatment:

  • Transection (via episotomy)
• Pain at coitus - vaginal hyperplasia

  Exaggerated response of the vaginal wall to normal oestrogen concentrations during oestrus:

  • Ventral vaginal thickens
  • May prolapse
  • Occasionally is circumferential.

  Clinical signs:

  • A mass at the vulval with the bitch in oestrus
  • Pain at attempted coitus.

  Treatment:

  • Conservative (disappears end of oestrus).
  • Surgical resection
  • Ovariohysterectomy for prevention
• What are the causes of failure to mate in the female?

  Not presented at the correct time

  Inexperience/ too shy

  Normal oestrus behaviour is not allowed to be displayed (inadequate time)

  Size differences

  Female pain at coitus

  Previous bad experience
• What are the causes of failure to mate in the male?

  Inexperience/ too shy

  Inadequate libido

  Musculoskeletal pain

  Previous bad experience

  Penile/ preputial abnormality

  Erection failure.
• Optimal mating time in the bitch

  Ovulation can vary between day 5 and day 32.

  Poor relation between behaviour and endocrinology.

  owner often ‘selects’ day to breed.

  Optimal time is within ‘fertilisation’ or ‘fertile’ periods.
• Reasons for failing to stay pregnant in the bitch

  In order of most common:

  • Inappropriate mating time.
  • Male factor infertility
  • Abnormal uterine environment
  • Infectious causes of pregnancy failure.
• Abnormal uterine environment - CEH

  Cystic Endometrial Hyperplasia

  • Hyperplasia occurs during each luteal phase in preparation for supporting the pregnancy.
  • Commonly the uterus does not return to the same histological appearance at the end of the luteal phase.
  • There appears to be an age-related change where areas of the endometrium are hyperplastic.
• Abnormal uterine environment - cystic endometrial hyperplasia

  Ultrasound documentation of CEH is common in bitches that fail to get pregnant.

  Condition may lead accumulation of sterile fluid within the uterus.

  The uterine environment is hostile and pregnancy does not establish or fails.
• Cystic endometrial hyperplasia/ pyometra

  CEH occurs with or without mating (it is associated with exposure to progesterone).

  May progress ultimately after a number of cycles to clinical pyometra (pus in the uterus).

  Pyometra may be seen in mated and non-mated bitches.

  Pyometra is normally only seen in mated queens
• Why is pyometra only normally seen in mated queens?

  If the queen is not mated she normally does not ovulate and so there is no progesterone to drive the pyometra.
• What can induce a pyometra?

  Therapeutic administration of oestrogen for treatment of unwanted pregnancy.

  Therapeutic administration of progestogens for prevention of oestrus.
• What is the definition of intersexuality?

  Abnormalities of chromosomal, gonadal or phenotypic sex.
• Clinical presentation of phenotypic female

  Clitoris enlarges at puberty

  Odd shaped vulva (often positioned more cranially)

  Male behaviour.
• Clinical presentation of phenotypic male

  Small penis with slit-like prepuce that may be more caudal.

  May have penile bleeding (oestrus).

  May have other lesions (e.g. hypospadias)

  May develop pyometra.
• Intersexualities in males

  Often purchased as a male, may later find no scrotal testes, or small testes on palpation.

  Commonly have tubular abnormalities so no ejaculation and if any abnormal sperm.

  May have uterus and if there are ovo-testes may come into oestrus (red discharge from penis).

  If ovulation occurs and there is a uterus a pyometra may develop.
• Intersexuality in females

  Often purchased as a female, clitoral enlargement is noted when it protrudes at the time of puberty.

  Some cases have minor clitoral enlargement, but have other dectable abnormalities of the external genitalia including small diameter vestibule.

  Most cases do not cycle and thus differential diagnoses for primary anoestrus.
• Treatment of intersexuality

  Removal of reproductive tract including glands is necessary:

  • Female - clitoris may reduce in size after gonadectomy and may then no longer protrude, but later clitoridectomy may be necessary.
  • Male mainly reducing the risk of pyometra is important.
• Bacteriological/virological screening in the dog

  There is no routine screening for venereal pathogens (issues with Brucella canis screening because of the high false positive rate).

  Lesions on the penis/prepuce mucosa might have been viewed suspiciously for canine herpes virus.
• Bacteriological/virological screening in the tom cat

  May be screened for FeLV prior to mating since this can be transmitted via close contact.
• Observation of libido

  Sniffing, jumping and playing.

  First fraction ejaculated.

  Bitch stands and deviates tail.

  Rapid thrusting ,ove nets, penis partially eject but os penis maintains rigidity, erection starts after intromission.

  Second fraction ejaculated, swelling of the bulbus glandis inside the vagina.

  Dog turns to face caudally, penis twists 180 degrees, third fraction is ejaculated.