Infertility Flashcards
What are some congenital anatomical causes of female infertility?
Ovarian hypoplasia
Reproductive dysplasia
Free-martinism/Inter-sex
Persistence of hymen (mare)
What are some acquired anatomical causes of female infertility?
Adhesions (e.g. Ovario-bursal, hydrosalpinx)
Endometrial fibrosis
Cystic endometrial hyperplasia (bitch)
Reproductive tract neoplasia (uncommon)
What are some pathophysiological causes of female infertility?
Ovarian pathology
Uterine infection
Failure to establish pregnancy
What are the typical presentations of a pathological ovary?
Oestrus not observed (ONO)
Barren/empty at pregnancy diagnosis
Persistent oestrus
Irregular oestrous cycles
What are the underlying causes of a pathological ovary?
Lack of normal follicular growth/oestradiol
Lack of GnRH/gonadotrophin
Lack of LH surge
Lack of endometrial PGF2A production
(Remember: underlying (patho)physiology might explain this (i.e severe negative energy balance, stress, prolonged prolactin, hypothyroidism))
What diagnostic methods are used for pathological ovaries?
Hormone analysis (progesterone)
Ovarian (uterine) palpation
Ovarian ultrasonography
(Accurate diagnosis can be tricky, esp. with cystic ovarian disease)
What are the types of pathological ovaries?
Anovulatory anoestrus
Cystic ovarian disease
Persistent CL
Describe Anovulatory anoestrus (pathological ovary)
Cow, dog, pig, mare
Lack of cyclicity
Delayed return post-partum / season
Associated with NEB
After pregnancy failure (mare)
Describe cystic ovarian disease (pathological ovary)
Cow, sow
Follicular structure that fail to ovulate and persist
- Follicular or Luteal
Describe persistent CL (pathological ovary)
Cow, mare
Failure to return to oestrus
CL persists in absence of pregnancy
What are the treatment strategies for pathological ovaries?
Promote ovarian function with gonadotrophins (GnRH, eCG)
Mimic luteal phase with progesterone
Induce luteinisation with GnRH/LH
Induce luteolysis with PGF2A
What are common infections affecting female fertility?
Endometritis, cervicitis, and vaginitis
When do reproductive infections commonly occur?
Post-partum (retained fetal membranes, dystocia) or post-mating
What are the effects of reproductive tract infections on fertility?
Subfertility, reduced conception rates & adverse effects on ovarian function
What are common treatments for reproductive infections?
Uterine contraction stimulation & antibiotics
What are some common causes of conception failure? (failure to establish pregnancy)
Inappropriate timing of AI/mating
Delayed (or lack of) ovulation
Chromosomal abnormalities
What are some common causes of early embryonic death? (failure to establish pregnancy)
Poor embryonic development
Failure to secrete maternal recognition signal
What management factors influence female infertility?
Oestrus detection accuracy
Timing of mating/AI in relation to ovulation
Number of matings (queens)
Ram:ewe ratio
Seasonality and lactation effects
Stress (handling, heat, transportation)
How does negative energy balance affect female fertility?
It can cause anovulatory anoestrus & second litter syndrome by reducing gonadotropin (FSH & LH) & IGF-1 levels, impairing ovarian function & embryo development
Why is IGF-1 important for fertility?
IGF-1 links metabolism & reproduction, influencing GnRH secretion (hypothalamus), FSH/LH release (pituitary), follicle growth & steroid production (ovary) & embryo growth & IFN-τ production
Which minerals affect female fertility and how?
Copper & Molybdenum toxicity → Impaired reproductive function
Selenium deficiency → Poor embryonic development
How do diet-related factors influence female fertility?
Oestrogenic plants (e.g. red clover) → Disrupt normal reproductive hormones
High dietary protein → Increased plasma urea, toxic to oocytes & embryos
Define fertility, sterility, subfertility, and infertility
Fertility: Ability to produce offspring
Sterility: Absolute inability to produce offspring
Subfertility: Below-average ability to reproduce
Infertility: Inability to achieve expected reproductive success (not absolute sterility)
How can causes of male infertility be classified?
Abnormalities of coitus
- Immaturity and inexperience
- Inability or unwillingness to mount
- Inability to achieve intromission
- Haemospermia
Failure of fertilisation
- Testicular disease
- Sperm abnormalities
- Epididymal lesions
- Accessory gland disease
(Each of these have subcategories)
What conditions prevent successful intromission (penetration)?
Breeding soundness examination
- clinical exam
- collect & evaluate semen
- ultrasound exam
What can you see in this semen evaluation?
Abnormal sperm (mid piece deviation & some dead sperm)
Cow is 100 days in milk. Farmer observed oestrus during voluntary wait period but has not observed signs since. She is clean on vaginal exam & rectal ultrasonography of ovaries reveals this.
What is your diagnosis?
What do we do next?
What is your diagnosis?
- Only small follicles visible
- No active structures on ovary, possibly anoestrus but difficult to say on one visit alone (could have ovulated too early for CL detection)
What do we do next?
- OvSynch protocol (mimic luteal phase & allow gonadotrophins to build up)
Cow is 50 days in milk. You perform a vaginal & rectal exam (plus ultrasonography). Results are displayed in images
What is your diagnosis?
How do you treat it?
What are the risk factors for this diagnosis?
What is your diagnosis?
- Can see that uterus is filled with fluid and speckles
- Endometritis (>21d in milk)
How do you treat?
- Depends on severity, options include prostaglandin, oxytocin & intrauterine antibiotics
What are risk factors for this diagnosis?
- Dystocia at calving, NEB, poor herd hygiene, retained fetal membranes
How is endometritis classified?
Grade 0-3 based on appearance of discharge
- 0 = clear mucus
- 1 = mucus containing flecks of white pus
- 2 = exudate containing <50% white mucopurulent material
- 3 = exudate containing >50% white/yellow (sometimes sanguineous) purulent material
Cow is presented at 70 days in milk. She is reported to have high activity on her pedometer & displaying signs of nymphomania.
What is your presumptive diagnosis? Why?
How do we treat this?
What is your presumptive diagnosis?
- Follicular cyst
Why?
- Large fluid filled structure, thin walled, history of nymphomania
How do we treat this?
- Options include GnRH, progesterone implants & synchronisation programmes
Why do we measure testes size?
Indicator of sperm producing ability
Smaller testes = less fertile
What impacts on testicular size of rams?
Body weight, age, breed, blood testosterone/gonadotrophin concentration, photoperiod, season of birth (smaller in summer) , nutrition
What are the 5 T’s of ram MOT?
Toes, teeth, testes, tone, treatment
Why is perineal conformation important for fertility in mares?
Poor conformation (e.g. shelving perineum) increases risk of pneumovagina, fecal contamination & ascending infections, which can impair fertility
What is the most common bacterial cause of endometritis in mares?
Streptococcus equi subspecies zooepidemicus
How is endometritis diagnosed in mares?
Uterine swabs for cytology & culture
Ultrasound showing fluid accumulation in uterus
What clinical sign indicates a bitch is in proestrus?
Vulvar swelling & bloody discharge
What is the best way to determine the optimal breeding time in bitches?
Progesterone measurement & vaginal cytology
What type of cells are dominant during oestrus?
80% Anuclear superficial epithelial cells (cornified cells)
When is the best time to breed a bitch after detecting the LH surge?
2 and 4 days post-ovulation
