Reproductive pathologies in the bitch and queen Flashcards
Disorders of the ovary.
Congenital abnormalities. (2)
Ovarian agenesis:
❖ Complete absence of one or both ovaries
❖ May be associated with other abnormalities such as uterus unicornus
Ovarian hypoplasia:
❖ Was reported in females with abnormal chromosome numbers
❖ Turners syndrome, chromosomal monosomy – 77 chromocomes (instead of normal 78 in dogs), only X
❖ Klinefelter’s, chromosomal trisomy – 79 chromosomes, XXX
Diagnosis by Karyotyping.
Females with anomalous numbers of sex chromosomes and abnormal ovaries are
usually infertile.
Describe Ovarian cysts. (5)
Follicular cysts are most often described.
Luteal cysts
Cystic corpora lutea: rarely reported
Germinal cysts: cysts of surface epithelial structures → doesn’t impair the
ovarian function.
Paraovarian cysts: cystic structures in remnants of the mesonephric and
paramesonephric tubules → are not reported to impair ovarian function.
Describe Follicular cysts. (6)
Thin walled, structures containing clear, serous fluid.
Often 1-1,5 cm in size (but reported to be 0,5-19 cm). (normal follicle 0.8 mm)
Pathogenesis is unknown
Mean age at diagnosis of bitches are 8 years.
Heritability is unknown
Lining of granulosa cells in the follicular wall produces estrogen → estrogen-mediated effects.
Clinical signs of follicular cysts: (6)
Related to increased estrogen levels:
❖ Prolonged proestrus or estrus
❖ Irregular inte restrus intervals (often short)
❖ Attraction of male dogs – but no normal breeding behavior
❖ Serosanguinous vulvar discharge
❖ If prolonged exposure of estrogen to the endometrium → risk of pyometra
❖ Bilaterally symmetrical alopecia may be present
Treatment of follicular cysts. (4)
❖ Treatment of choice is ovariohysterectomy
For valuable breeding dogs, induction of luteinization:
▪ GnRH 50µg IM
▪ hCG 220IU/kg IV or 500IU IM two doses with 48 hours interval CHECK DOSER Limited effect has been reported.
▪ Resection of the cyst or removal of one ovary if only unilateral.
Minimum good inter estrus interval?
4-5 months
definitely not less than 4 but more than 5 is okay
Describe Vaginal hyperplasia. (6)
Extreme response to normal estrogen concentrations that results in:
- Edema of often the ventral wall of the vagina in front of the urethra opening
- The protrusion is tongue-shaped with a wide base of attachment, it can sometimes protrude extensively throughout the vulva lips.
- Symptoms occur during proestrus or late pregnancy.
Symptoms:
- Self-licking
- Self-trauma and the tissue gets inflamed and cracks
- Symptoms regress when estrogen decreases and progesterone increases after ovulation.
- If the bitch gets pregnant it will normally resolve before parturition.
Describe Vaginal hyperplasia therapy: (4)
- Usually conservative→ prevention of self-trauma and use lubricative cream, eventually GnRH/hCG to induce ovulation.
- Ovariohysterectomy
- Surgical resection of the hyperplastic tissue can be necessary in extreme cases.
- For pregnant bitches the hyperplasia will normally not contribute to dystocia.
Describe Ovarian remnant syndrome. (2)
A syndrome that occurs when a retained piece of ovarian tissue revascularizes and becomes functional → clinical signs of functional ovarian tissue.
The retained piece of tissue is due to:
❖ Surgeon error
Clinical signs of Ovarian remnant syndrome. (3)
❖ Signs of estrus (vulvar discharge and edema, attraction of males …)
❖ Interval from OHE → signs of estrus → average 15,5 months (3m-5y)
Differentials:
❖ Vaginitis, stump pyometra, vaginal neoplasia, coagulopathy, exogenous estrogen therapy
Diagnosis of Ovarian remnant syndrome. (5)
+tx
❖ Vaginal cytology → cornified epithelium
❖ Ultrasound → can be difficult to visualize small amounts of tissue
❖ Once presence of estrogen has been verified → serum progesterone in blood 2
weeks later.
Luteinization of the tissue:
▪ GnRH 50µg or hCG 400IU iv or 1000IU (half iv/half im) → recheck of progesterone
concentration in 2 weeks.
❖ LH testing (when the bitch is not in estrus → do smear) → if low, then no negative feedback → remnant of ovarian tissue.
❖ AntiMullerianHormone testing→ indicates presence of granulosa cells.
Treatment: explorative laparotomy and removal of ovarian tissue.
Describe Ovarian neoplasia.
Relatively uncommon but easy to diagnose.
Can be palpable per abdomen and are visualized by ultrasound:
❖ Rounded or irregular masses caudal to the kidney with variable texture.
Differentiated into:
❖ Epithelial tumors: adenocarcinomas, papillary adenoma .. etc.
❖ Sex cord/stromal tumors: granulosa cell tumors(GCT), thecal cell tumors, luteomas
❖ If GCT → increased estrogen/ progesterone, non-reg.anemia,
thrombocytopenia, estrus signs
❖ Germ cell tumors → if the fertilized ovum differentiates into extraembryonic tissues → development of germ cell tumor (teratomas, ovarian seminomas).
Mucometra/hydrometra.
Accumulation of sterile serous or mucoid fluid in the uterus.
The bitches are asymptomatic so usually incidental findings at the time of elective OHE.
Pathogenesis:
Secretion of progesterone during several diestrus periods → increases secretory activity of the endometrial glands→ closes the cervical entrance→ accumulation of fluid/mucus in the uterus.
CEH =
Cystic endometrial hyperplasia (CEH)
CEH is considered an important predisposing factor to pyometra due to:
formation of endometrial cysts & proliferation and growth of endometrial glands
During proestrus/estrus→ bacteria from the vagina moves into the uterus→ the
normal uterus are able to clear the uterus from bacteria prior to the luteal
phase (diestrus).
In dogs with CEH this is not happening→ secondary infection with normal
opportunistic bacteria from the vagina that are invading the endometrium→
pyometra.
❖ CEH is caused by repeated exposure of the endometrium by progesterone during diestrus.
❖ The progestogen effect is enhanced by priming the endometrium with estrogen during estrus.
But the 2 conditions can develop independently too.
The uterus in the normal bitch is sterile when? (3)
proestrus
estrus
post partum
Clitoris hypertrophy. (3)
Can occur secondary to inflammation,
self-licking, edema
Hormone dependent hypertrophy (bitch treated with progestogens during pregnancy)
INTERSEX individuals → check for os clitoris → do karyotyping (pseudohermafrodites/ true hermaphrodites)
