Lecture 22,23 - Functional Infertility (endocrine disorders of reproduction) Flashcards
How do inactive ovaries lead to functional inferitlity?
No egg to fertilize - anovulation
How do silently active ovaries lead to functional infertility?
No breeding
How can you determine if ovaries are active?
Palpation and U/S
If the female has never shown signs of estrus, and her ovaries are not currently active, what are 4 differentials?
Seasonal anestrus
Chromosomal abnormality
Anabolic steroid therapy
Prebuberal
If we know a calf was born co-twin to the opposite sex, examine the female within the first 30 days after birth with a test tube. What do the results indicate?
If a 10 mL test tube will not pass to full length of the vagina, the cow is a freemartin
How to detect prepubertal animals
Weigh heifers/ewe lambs - if female weight is not at least 60% of her anticipated adult body weight, most likely pre-pubertal.
Reproductive tract scores in beef heifers
Concept of reproductive tract scores in beef heifers
Formal process in which we try to estimate whether the heifer has gone through puberty or is close to going through pubery (based on 1-5 scorying system).
The lower the score, the further she is from being a cycling female.
What is the main thing a cow will have that will determine if she has gone through puberty?
A CL
Alpacas can reach puberty at any time between __ and __ months.
18-36
If a female has never shown signs of estrus, and her ovaries are currently active, then she must be in ______ ______.
Silent estrus
Reasons for silent heat in a cow?
Post partum, hot weather, disease, Bos indicus breed, housing
Reasons for silent heat in the ewe
First cycle of the season
Reason for silent heat in the mare
Foal by side
Silent heat can be easily mistaken with ________
Poor teasing/heat detect
If a female has not shown signs of estrus during hte last few months, but has shown estrus previously, what question do you need to ask next?
Is she pregnant
If a female has not shown signs of estrus during hte last few months, but has shown estrus previously, is not pregnant, and does not have active ovaries, what are your differentials?
Seasonal anestrus
Lactational anestrus
Pituitary tumor
Severe malnutrition
Persistent endometrial cups (mare)
Three things that dictate true anestrus that can be found on transrectal palpation and U/S:
No ovulatory follicles
no CL
No cycles
Reasons for true anestrus:
- Poor nutrition (dairy cow)
- Lactation (beef cow, sow)
- Normal in bitch up to 12 months post partum
- Season
- Pituitary tumor
- REproductive sensecense
How do pituitary tumors lead to anestrus?
supress ability of the pituitary to release LH and FSH
If a female has not shown signs of estrus during hte last few months, but has previously shown signs of estrous, is not pregnant, and only has one ovary active (one larger, and one inactive), list the differentials:
Granuolsa cell tumo
Cystic ovarian disease
T/F: Granuolsa cell tumors are an old animal cancer.
False!!
Granuolsa theca cell tumors occur in virutally all species. However, what two species in particular do they play an improtant role in?
Horse and dog
Granuolsa-theca cell tumors give rise to increased levels of _____ in the dog.
estrogen
Dogs with GTC tumor wil persistently be in what stage of their estrous cycle?
Proestrus
Why do dogs present with anemia with a GTC tumor?
Persistently in proestrus due to hyperestrogenism (estrogen secreted by the tumor) - losing so much blood through leakage from the endometrium
By the time the mare is presented to the vet with GTC tumor, why do they behave “male” like?
Horses initially go through a persistent estrus phase when the GTC tumor secretes a lot of estrogen, but this phase is so short that it often goes unrecognized by the client. By the time the client brings them in, the granuolsa cells become metaplsastic and change their function, losing their ability to convert androgens into estrogens. So now the precursor to estrogen (testosterone) piles up.
Why do GTC tumors inhibit the contra-lateral ovary?
Becuase along with estrogen, they also produce inhibin.
Do granuolsa cell tumors ever lose their ability to produce inhibin? What are the consequences?
No, so FSH concentrations are rock bottom low - resulting in complete inactivity of the contralateral ovary.
Upon rectal palpation of the mare, in order to diagnose she has a GCT - what two things must you confirm?
- Large affeted ovary with NO OVULATION FOSSA
- Inactive contra-lateral ovary
What hormones can you test in the mare for GCT?
- Inhibin - high with GCT
- Testosterone - usually high with GCT
- Progesterone - absence with GCT (not cycling)
- AMH - high (GCTs secrete AMh as well)
Treatment for GCT?
Removal of the ovary
Cystic ovarian disease is a disease of which species?
Cattle
T/F: the horse may suffer from cystic ovariaion disease.
FALSE - HORSES NEVER GET CYSTIC OVARIAN DISEASE
A cows CL is highly vascularized. Upon U/S, it shoudl appear as ____ (hypoechoic or anechoic or hyperechoic).
Hypoechoic
What is a cystic CL, and what should a “cystic” CL be referred to? Why?
A cystic CL is a developmental stage of the young CL, and it should be referred to as a hollow or cavitous CL b/c it is stil a CL but with a fluid filled cavity inside of it.
On U/S, a cystic CL appears _____ (hypoechoic, anechoic, or hyperechoic).
anechoic - fluid filled center
is a “cystic” CL in the bovine equivalent to cystic ovarian disease?
NO! Cystic CL are normal - developmental stage of the CL!!!!!!!
Three criteria of cystic ovarian degeneration
- Fluid filled structure > 2 cm
- persisting for more than 14 days
- Anestrus
What are the two types of cysts in cystic ovarian degeneration in the bovine that result from ovulatory failure of a graffian follicle?
Follicular cyst
Lutenized cyst
How does a follicular cyst form? Describe a follicular cyst
A persistent follicle that was exposed to inadquate LH surge
Thin walled, almost translucent
Keep growing b/c granuolsa cells keep producing fluid, until the granuolsa cells die from the high pressure, leaving behind the thecal cells. The thecal cells keep producing testosterone, which cannot be converted into estrogen by the granuolsa cells. Male-like clinical signs form as a result.
How does a lutenized cyst form? Provide a description
a lutenized cyst received enough LH to become a luteal structure, but unlike a CL, persists even in the presence of PGF2a.
On U/S, the walls are thickened around the fluid filled cavity - looks like a CL.
Usually only one present.
Bovine cystic ovarian disease occurs most commonly when?
Post-partum
Bovine cystic ovarian disease results from an ___ deficiency.
LH
Treatment of bovine cystic ovarian disease
GnRH - 7 days - PgF (OvSynch!)
or
PGF only (for luteal cysts)
or
CIDR-OvSynch
Canine cystic ovarian disease results in hyper-_____ and persistent ____.
Estrogenism; estrus
Canine cystic ovarian disease is usually ______ (bilateral or unilateral)
Bilateral
Due to persistent blood loss from being in estrus, a bitch with canine cystic ovarian disease often has _____ as a result.
Anemia
Tx of canine cystic ovarian disease
Attempt to induce ovulation with hCG or GnRH - not great
Best tx = spay
If a bitch has not been in estrus for several months, should we jump to the conclusion that she has canine cystic ovarian disease?
NO! This is uncommon in dogs, and hte bitch is in anestrus by default (unlike the cow, where anestrus is a sign of disease). So unles syou have U/S evidence for polycstic ovary, do NOT go to this dx.
T/F: Endocrionlogically inert ovarian tumors are a part of functional infertility.
False because cancers of the ovary do not produce hormones and will not dirsupt cyclicity of the female. However, in our efforts to diagnose functional infertility, we might end up finding this disease.
Endocrinologically inert ovarion tumors will not interrupt cycles until ovary is ______ completely by the tumor.
destroyed
T/F: In canine papillary adenocarcinomas on the ovary, the cancer usually metastasizes and disrupts ovarian function.
False - hardly ever metastasizes, and usually does not dirrupt ovarian function (i.e. a CL can still form)
Do we rely on the ovary to make a diagnosis of lymphoma in bovines?
No, long befor eit causes pressure atrophy of functional ovarion tissue, it will spread and compromise the well-being of the cow. Therefore, we usually find the tumor somewhere else when diagnosing.
Most common ovarian tumor in the equine?
Teratoma
Teratomas originate from ____ tissue.
Embryologic
Teratomas are more common in ____ testes.
retained
An equine ovarian hematoma is endocrinologically _____.
Inactive
How does an equine ovarian hematoma form?
Follicular fluid contains anti-coagulants, so if a hemorrhage were to occur into an intact follicle, the bleeding would not stop, resulting in a gigantic hematoma.
Diagnosis of equine ovarian hematoma?
U/S - see a large fluid filled structure - echoic due to blood
Equine hemorrhgaic anovulatory follicles (HAF) are sometiems referred to as ______ follicles.
Autumn
What are equine hemorrhagic anovulatory follicles?
Uncoagulated blood (echogenic specs) inside an oversized follicle with luteinizing wall
Equine hemorrhagic, anovulatory follicles are functionall no different from ___ after ovulation.
CL
In an equine hemorrhagic anovulatory follicle, even though it is functionally no different form CL after ovulation, does the oocyte eventually leave the follicle?
No, the large follcile simply develops trabeculae in the lumen until eventually it becomes a CL without ovulating the oocyte.
T/F: Equine hemorrhagic, anovulatory follicles usually result in dirsuption of cyclice activity.
False
How is a corpus hemorrhagicum different from an equine hemorrhagic, anovulatory follicle?
Upon U/S, there is no swirling of unclotted blood in the corpus hemorrhagicum, like there is in the HAF. This is becuase a blood clot forms within 12-42 hours after ovulation of a normal sized follicle, and the coprus hemorrhagicum develops into a regular CL.
If a female has not shown estrus during hte last few months, but has shown estrous before, is not pregnant, but BOTH ovaries are active, what are her differentials:
Silent estrus
Persistent CL
Pregnancy that went unnoticed at first
Reasons for luteal persistence:
- Spontaneous
- Damaged endometrium
- Pseudopregnancy (embryonic death after recognition of pregnancy)
- Diestrus ovulation (only in horses)
- Persistent Endometrial cups in the horse
Diestrus ovulation occurs only in what species? ANd what can it lead to?
The horse - persistent CL
Pseudopregnancy type I in equine occurs between the window of fixation (maternal recognition of pregnancy) and formation of _______. This is specifically between days ____ and ____.
Endometrial cups (16-35)
How can a damaged endometrium lead to luteal persistence?
Unable to secrete sufficient PgF to induce luteolysis
WHat is diestrus ovulation in mares?
The dominant follicle of hte first follicular wave after ovulation ovulates, instead of becoming atretic. So P levels never reached basal concentrations for the mare to come back into heat, and she simply started a new progesterone profile.
Pseudopregnancy type II occurs when the fetus dies after day ____ in the mare. Why?
35 - occurs after the formation of endoemtrial cups, which will continue to produce eCG (LH-like) - producing accessory CL on the ovary as a result. This process will not end until the endometrial cups go away - at about 100 days post ovulation.
Treating a pseudopregnancy type II
Destroy endometrial cups with a laser beam
Is it possible for endometiral cups to persist throughout pregnancy until term and even after foaling in the mare and therefore secrete sufficient eCG to prevent hte mare from cycling?
Very rarey
Luteal peresistence is commonly associated with _____ in the bovine and canine.
Pyometra
Luteal persistence is commonly associated with _____ in the caprine. How?
Hydrometra - luteal persistence is the CAUSE of hte hydrometra - where under the influence of P, the endometrium continues to secrete uterine milk and no conceptus to consume this uterine milk, and therefore accumulates and the uterus becomes distended.
Note - hydrometra can occur in any animal, but classic int he goat
Luteal persistence is commonly associated with _____ in the horse.
Endometrial fibrosis/endometrosis - permanent damage to the endometrium - less capable of producing PgF to induce luteolysis
WHat is the tx for luteal persistence? Exception?
Tx - PgF
Except with persistent endoemtrial cups - these can be removed by endoscopically guideded laser
If you see multiple CLs in the horse that has had a history of being pregnant, or at the minimum of having been bred over 35 days ago, it is a rason to suspect she has ______.
persistent endometrial cups
If a female has shown signs of estrus during the last few months, but her interestrus intervals are not normal, and has not been bred, what are her differentials?
Transitional estrus
Split estrus
Endometritis
Endometrial fibrosis
What is the single most common diagnosis in horses that get sent to vets for ovariectomy because the practitioner suspected a granuolsa tehca cell tumor b/c the ovaries looked like polycystic ovaries? How can you distinguish b/w the two?
Transitional estrus - easy to distinguish b/c BOTH ovaries are involved, and BOTH ovaries are normal in size/palpable.
The presence of a dominant follicle in the absence of endoemtrial edema suggests _______ in the mare.
Transitional estrus
Why do we not have endoemtrial edema in transitional estrus?
The dominant follicles secrete less estradiol than they would in normal estrus, therefore there is not enough estradiol the produce sufficent visible endoemtrial edema.
Will a mare likely ovulate during transitional estrus when we give her exogenous hCG or GnRH if she does not have endometrial edema present on U/S? Why?
Probably not, becuase the dominant follicles in transitional estrus secrete less estradiol. Estradiol is required to induce LH receptors on the follicles, so with less estradiol, there are not enough LH receptors to respond to an LH surge induced exogenously (whether it is hCG or GnRH), and the follicles will not ovulate.
When do you know you can give a mare hCG or GnRH to induce ovulation at the end of transitional estrus?
When you can see endoemtrial edema on the U/S - means enough estradiol is being produced to stimualte enough LH receptors on the follicles
Treatment for transitional estrus in the mare?
Altrenogest, progesterone in oil, or Progesterone & Estrogen protocol
What is split estrus in the canine?
IT occurs regulary in the bitch, and is when she comes into proestrus, but never ovulates, and therefore never enters estrus, and skips right into cytological diestrus. There is no LH surge, no rise in serum progesterone, no ovulation. Proestrus will start again 1-4 weeks later.
Is split estrus usually normal in canines?
Yes
How to diagnose split estrus in the canine
Look at vaginal smears - can see cytologically that she goes from proestrus straight into diestrus (skipping over estrus)
Endometritis can cause premature luteolysis as a reuslt of ____ from uterine infalmmation. The Interestrus interval is therefore ______.
PgF; shortened
Endometrial fibrosis can cause delayed luteolysis as a result of failure of endoemtrium to secrete ____, and therefore the inter-estrus interval is ______.
PgF; extended
If a mare has shown signs of estrus during hte last few months, but has ireegular intervals of interestrus, and was bred, what are her differentials?
Examine tubular tract
Heat detection problem (bred at the wrong time)
If the females interestrus intervals are normal, are we dealing with a funciontal infertiltiy/endorcine dysfunction?
NO!
If the female has shown signs of estrus in the last fe wmonths, has regular interestrus intervals, and has been bred, but fails to fall pregnant, what is the problem?
- Pregnancy
- Abnormal semen
- Timing of AI or service
- Poor insemination technique
- Induced ovulation at erroneous time
- Poor semen handling
