24, 25, 26: fail to become detect preg - canine pyometra to end Flashcards
approximately how many breeding bitches will get canine pyometra?
2 in 400
why is canine pyometra a less common problem now what it used to be?
it is a well understood dz and is preventable, so is much less common overall now than it used to be
what is the definition of pyometra?
more than just pus in the uterus…..
a disease complex that includes the progression of:
cystic endometrial hyperplasia, mucometra (=hydrometra), endometritis and pyometra complex
what is the classic presentation for canine pyometra?
- middle aged, nulliparous FM
- late estrus 4-8 wks ago
- often treated w steroids for birth control
- treated w abx during previous heats
- gradual onset of dz
what is nulliparous?
never had offspring
what steroids are used to treat bitches for birth control?
- progestagens and estrogens
what is the role of progestagens in birth control?
to suppress estrus
what is the role of estrogens in birth control?
“morning-after” treatment for mismated bitches
how does the administration of p4 and e2 during pro estrus pre dispose the bitch to developing pyometra?
when p4 is added to suppress estrus, at a time when she is under the influence of e2, they have a synergistic effect on the endometrial glands and they produce excess ‘milk’
when there is no embryo present to consume the milk, it accumulates in the uterus -> cystic -> mucometra -> hydrometra
if a bitch presents with pymoetra and is not “classic”, meaning she is young and recently had a litter, what specifically should you ask about?
ask if she was treated with anti microbials when she was in heat last
why do some treat bitches with anti microbials while in heat?
some think bitch has better chance of conceiving if she is treated during estrus
some uneducated owners of male studs will demand the bitch be treated before mating to prevent spread of STI’s - which is incorrect b/c they do not exist in animals like they do in people and most pathogenic dzz would be spread by the male anyways….
what does giving a bitch antimicrobials while in estrus achieve?
selects for more resistant bacT and oftne more pathogenic bacT - to grow in her reproductive tract and wipes out commensal healthy bacT
what do you suspect happened to a young bitch that presents with pyometra and has an unusual bacT that is highly resistant to drugs?
she was probably given antimicrobials during her last heat cycle
what are c/s of bitch with pyometra?
lethargy dec appetite free fluid at time of preg diagnosis distended, tender abdomen enlarged lnn dehydration anemia
s/t (sometimes):vaginal discharge
PU/PD
vomit/diarrhea
collapse
in the bitch, why does vaginal discharge occur s/t but is often uncommon at time of onset of pyometra?
b/c she is still under the influence of p4, which holds the cervix closed
how does endotoxemia occur sometimes in the bitch with pyometra?
endotoxins are absorbed from the uterus -> affect uterus function -> cause PU -> PD as a result of the PU
only in about 1/3 of the cases
why do some bitches vomit and have diarrhea with they have pyometra?
b/c they are toxemic
if left unattended, why does a bitch with pyometra collapse?
multi organ failure occurs as result of endotoxemia -> death can occur if not treated
if free fluid is seen in the uterus of the bitch 3 weeks post breeding, what does that indicate is likely to occur?
pyometra
why might a bitch with pyometra experience hyperthermia followed by hypothermia?
hyperthermia - fever - due to infection
hypothermia in later stages - due to severe shock
when does peripheral lymphadenopathy occur in a bitch with pyometra?
3-4 wks after inoculation / initial infection by the time you see her
when / why does a bitch with pyometra experience anemia?
chronic infection
due to toxemia
what precaution must be taken if palpating abdomen of bitch with suspected pyometra?
palpate enlarged uterus
be cautious - b/c if the cervix is shut, the increased pressure from your palpation will put pus into the utero tubal junction and into peritoneal cavity -> pyometra becomes peritonitis [pyo abdomen]
what is a better alternative than palpating the uterus of a bith with possible pymoetra
u/s
when examining a bitch with pyometra, what do you see when conducting a vaginoscopy?
pus in the anterior vagina
what is seen on cytology from a bitch with pyometra?
many NTs, toxic NTs, NTs with phagocytossed bacteria
what use is culture for a bitch with pyometra?
more use if trying to preserve her breeding ability instead of spaying her - in this case, she needs to be treated medically instead of surgically
is difficult to do though, b/c you will get some resident bacT from anterior vagina
must know what is there in order to know how to kill it
what types of bacT tend to show up on culture of bitch with pyometra?
MC vaginal bacT
mostly opportunistic infection
70% e. coli
may see Proteus, staphs, klebsiella, pseudomonas, some anaerobes
t/f
a lab work up of blood work is necessary to definitely dx pyometra in bitch?
false
lab work is only necessary if you cannot make the dx based on hx and presentation
what chances to WBCs will be seen in bitch with pyometra?
acute and chronic changes
acute: neutropenia
chronic: neutrophilia with left shift
on CBC of pyometra bitch, why might hematocrit be increased? decreased?
inc: dehydration
dec: anemic
what does a urine specific gravity of a bitch with pyometra indicate?
supports PU
why might knowing a bitch’s BUN prior to Tx for pyometra be of value?
we may use potentially nephrotoxic drugs so knowing her kidney function ahead of time would be helpful
t/f
it is common to evaluate IgG and look for hypergammaglobulinemia in a bitch with pyometra
false
hypergammaglobulinemia will be seen in chronic cases of pyometra - not measured specifically or very often
how is pyometra diagnosed in the bitch?
- anamnesis
- uterine distention
- vaginal discharge
- leukocytosis
- cytology
- u/s
t/f
x rays are a common modality used to dx pyometra as well as other soft tissue dzz in the abdomen
false
u/s is better
x ray was used in past but should not be used anymore for soft tissue dzz
what is the best and most common treatment for canine pyometra?
ovariohysterectomy
t/f
canine pyometra is urgent and considered an emergency - surgery must be planned for that day
true
t/f
to reduce the risk of rupture and leakage, a small incision should be made to remove the uterus from, similar to a spay incision
false
incision should be very liberal and large so the uterus is not squeezed or handled roughly to be removed
t/f
during a spay of a pyometra bitch, the entire uterus and cervix is removed
true
how might peritonitis occur during surgery to treat pyometra?
- leakage through uterine tubes and into the abdomen
- rupture of uterus
what might occur if a stump of uterus with pus is left behind in a bitch?
stump pyometra or stump granulomas
what tissue should you ligate through to prevent stump granuloma from occurring?
the anterior vagina
t/f
it is necessary to stabilize the pyometra bitch before conducting surgery
false
not really appropriate b/c she is so toxic, she needs immediate supportive care and to head straight to surgery to remove the source of infection
what is the medical treatment of pyometra in bitch?
luteolysis
abx
fluids
NSAIDs
what luteolytic agent is MC used to Tx pyometra in bitch?
PgF2a
why is luteolysis a successful Tx for canine pyometra?
removes source of p4 which allows cervix to open so pus can drain when uterus is squeezed
when selecting which PgF2a drug to use for pyometra in the bitch, is chlorprostenol or luteolyse [dinoprost] a better option?
luteolyse is better b/c in a study with chlorprostenol, one dog died so if a dog you treat with it dies and the owner sues you, lawyers will find this study and use it against you
what are 3 appropriate dose regimens for dinoprost / luetolyse for tx of pyometra in bitch?
- 50 ug/kg BID s/c 1 day
- 100 ug/kg BID s/c 1 day
- 250 ug/kg BID s/c 5 days
what dose regimen for dinoprost / luteolyse is NOT appropriate for use b/c it is experimental and would leave you vulnerable as a practitioner?
why might some consider using it?
10 ug/kg QID s/c 7-10 days
it has no side effects
why are high doses of PgF2a required for luteolysis in a bitch?
risks?
very high doses required b/c canine CLs are very refractory to PgF2a
many side effects will occur to make bitch sick
t/f
RU 486 (algepristone or Mefipristone) is a readily available drug that is used commonly to cause lyteolysis in dogs with pyometra
false
RU 486 is illegal for use in animals in US b/c it is used for human abortions
used readily in Europe
in addition to lysing the CL, what other function does PgF2a have in canine pymoetra Tx?
it also serves as an ecbolic agent
what is MC antimicrobial used to tx canine pyometra?
side effects?
gentocin and penicillin
aminoglycoside => nephrotoxic
in addition to gentocin and penicillin, what other antimicrobials are used to Tx canine pyometra?
amoxicillin
clavulinic acid
enrofloxacin [less toxic than aminoglycosides]
in what way might steroids be used in some cases of pyometra?
shock doses of steroids if the bitch is very bad and you need immediate action to save her life -> this will stabilize her, then you can operate in 2 days
what is the prognosis for a pyometra bitch after medical therapy?
recurrence and fertility?
not great
10-30% recurrence
10-50% fertility [volkman says up to 80% fertility in his experience]
t/f
after experiencing pyometra and medical treatment, a bitch should not be bred in her next heat cycle
false
she SHOULD be bred in her next heat cycle - do NOT leave her uterus empty for another cycle
t/f
if after medical tx for pyometra a bitch is bred but fails to become pregnant, you should be concerned about persistent infection
false
persistent infection is unlikely
you should be concerned that the endometrium was damaged and that it might not be able to support a pregnancy
in an unspayed bitch, what is necessary in order to get pyometra?
steroidogenic priming of the uterus
what drugs are available as contraception in bitches?
megestrol acetate (ovaban) mibolerone
how does megestrol acetate work in the bitch?
put the bitch on the drug when she is in anestrus and does not have e2
how does mibolerone work in the bitch?
androgenic drug - testosterone like
suppresses HPA
**best Tx
what tumor occurs MC in the uterus?
lyommyoma - tumor of smooth muscle
what is the significance of endometrial cysts in mares? what does it indicate?
indication of endrometrosis
will block embryo - failure of maternal recognition of pregnancy (MRP)
interferes with placentation
t/f
endometrial cysts of the mare are cystic glands
false
they are lymphatic lacunae that are dilated / filled with lymphatic fluid
t/f
endometrial cysts indicate that the mare is unable to become preg
false
indicates that she has some damage to her endometrium, likely from other pregnancies
but she can still become pregnant
at what size is the endometrial cyst in the mare a concern for the movement of the embryo through the uterus?
3 cm
why might pregnancy fail in the mare due to endometrial cysts?
what can be done to help the mare achieve pregnancy despite the cysts?
the embryo cannot move around the endometrium therefore the mare cannot recognize pregnancy
7 days after breeding, put her on altrenogest - a progestagen - so she does not rely on the CL for MRP
if very large, endometrial cysts in the mare can interfere with placentation.
but more often than not, what occurs? why?
the placenta forms without problems b/c there is endometrium over the cyst
what do the fetal membranes look like in mares who have endometrial cysts foal successfully?
they look normal
no scarring - placenta attaches to endometrium over the cyst
how can cysts be treated?
surgical excision
historoscopic exam - laser beam removal
what is endometrosis?
how does this interfere with ability to get pregnant?
intra uterine growth retardation - glandular atrophy, fibrosis in large spaces of lymphatic fluid
leads to impaired placentation b/c less tissue available for placenta development enough to support a foal
what is the difference btwn endometrosis and endometriosis?
endometriosis is dz of women, uterine cells implant in to the abdomen and grow uterine tissue there
endometrosis = intra uterine growth retardation
if a foal is born to a mare with endometrosis what will it look like? what will fetal membranes look like?
foal - small, poorly developed, cripple - carried longer than term
membranes - show areas of massive absence of villi
what is the pathogenesis of hydrometra?
obstructed outflow of uterine milk
in what species does hydrometra MC occur?
goats
what condition in goats might lead to hydrometra?
persistent CL
what is the common presentation for hydrometra in the bovine?
white heifer dz in charlois breed
parts of tubular genitalia are occluded - trans luminal mem separating uterine horn from cervix, trapping the uterine milk
often found in virgin animal
Tx for hydrometra due to retained transluminal mem in bovine?
prognosis?
remove the membrane and she will be okay
what is uterus bicollis?
what species?
congenital mal formation of cervix occasionally seen - duplicated cervix
rare but MC in mare
what lesion of the cervix is MC than uterus bicollis?
significance of this condition?
MC is acquired traumatic lesion - does not open and close as it should bc it is partly fibrosed and does not respond to endocrinologic stimulation
therefore will not close during pregnancy and will allow bacT to enter - placentitis or endometritis will recur - preg unsuccessful or will not occur
what predisposes animals to pneumovagina and urovagina?
what condition ensues?
what issue does this lead to? and in what species MC?
MC an issue in horse and dairy cow - important source of infertility
loose supportive tissue in perineum - anus gets pulled farther into the pelvic cavity - pulls vulva up - vulva stretched over ischiatic arch - renders vulva less than optimally competent to closing - bacT can enter
if vagina has downhill slope to cervix instead of towards to vulva, the vestibular sphincter is compromised, urine can pool in the vagina
what c/s can occur with pneumo and uro vagina?
urine scalding in mare w uro vagina
inflammed vagina or uro vagina
what Sx Tx for pneumo and uro vagina?
Caslicks Sx
extend urethra in Cd direction - make artificial tunnel from existing urethral opening to somewhere close to the vulva - simple but NOT easy
what are transluminal adhesions in the vagina caused by?
MC caused by intra partal trauma
often dystocia causes it
tissues can grow together and can cause hydrometra
what is the origin of transluminal bands?
muellerian tubes that fail to completely fuse to make a single vagina
at what level of the repro tract to trans luminal bands occur?
at the level of the vestibulo vaginal junction
tx of transluminal bands?
can often be easily broken by veterinarian or copulation if thin
or thick, may need transection
what is vaginal hyperplasia?
excessive proliferation [hypertrophy and hyperplasia] of the floor of the vaginal epithelium under the influence of e2
tissue in Cd vagina and vestibule especially sensitive to effects of e2
in what species and breeds is vaginal hyperplasia MC?
heritable?
brachycephalic dogs - Eng bull dog, boxer, boerbull
yes - heritable
how does vaginal hyperplasia affect ability to breed?
prevents intromission and natural service
best Tx for vaginal hyperplasia?
spay the bitch
why does vaginal hyperplasia s/t occur near the end of pregnancy?
significance?
high e2 levels stimulate it
cannot give birth - dystocia - c section often necessary
what transmissible tumor of the vagina/vulva occurs?
TVT - transmissible venereal tumor
what is unique about cellular structure of TVT cells?
cells have abnormal # of chromosomes
how is TVT spread?
contact and licking
t/f
TVT can spread to the mouth and skin via licking?
true
t/f
TVT is very malignant
false
- usually spontaneously regress w/in a few mos
- if not, TVT is very responsive to vinchristine chemotherapy
best Px measure for TVT?
Px roaming - no free sex
or spay and neuter
what is common presentation of puppy vaginitis?
pre puberal bitches
mostly large breeds
what is pathogenesis of puppy vagainits?
unknown
t/f
in the case of vaginitis, the bitch should be spayed immediately
false
wait until the vaginitis is resolved to spay the bitch
best Tx for vaginitis?
none - self cure very common - dependent on endocrine effect of coming into heat
t/f
systemic vaginitis should be treated with systemic abx?
false
flush vagina with some dilute antiseptic solution - flush until cleaned out
t/f
finding bacT in the vagina is grounds to dx vaginitis in a breeding bitch
false
every vagina is very populated by commensal bacT
t/f
vaginal cultures of breeding bitches is routinely indicated
false
NOT routinely indicated
t/f
mycoplasma contributes to sub fertility
false
old reports - no longer found to be true
t/f
before breeding, a FM should be given abx to clear out her repro tract and px the spread of STI’s to the M
false
NO KNOWN STD’s other than brucellosis
what is the etiology of Tritrichomonas fetus? [Trich]
protozoa
mobile anaerobe
how is Trich transmitted?
coitus via infected semen
old or young bulls are carriers of Trich?
older bulls are carriers
young bulls under 3 yo self cure
t/f
Trich infected bulls are always subclinical
true
t/f
cats can become infected with Trich
true
what is the manifestation of Trich in cats?
can cats transmit the dz to cattle
GI dz
cats are NOT shown to be source of infection in cattle
what is manifestation of Trich in cows?
transient endometritis
failure to become pregnant
specifically, how/when does the Trich prevent cow pregnancy?
initial conception occurs
gradual endometritis leads to embryonic death AFTER maternal recognition of pregnancy
why does a cow infected with Trich often have delayed return to estrus?
b/c MRP has already occurred
t/f
a cow will self cure from a Trich infection
true
how long does it take a cow to self cure from trich?
3 cycles
after 3 cycles, how is a cow affected by Trich long term?
self cured so immune
return to complete fertility
if a cow is re exposed to Trich after curing herself of first infection, what happens?
why?
accelerated self cure at subsequent exposure
she has Tc cells that recognize and clear the infection faster
what is the preg rate of exposure to Trich in naive herds?
as low as 30%
increases after longer breeding seasons with preponderance of early pregnancies resulting from breeding after self cure and immunity
in herds with endemic infections of Trich, what is the preg rate?
up to 80%
erosion dz - people learn to live with it
t/f
Trich is a reportable dz
true - in MO and a lot of other states but not everywhere in US
note: considered eradicated in other countries
best way to keep Trich out of cow herd?
test bulls
what is the Trich test for bulls?
what sample of tissue and what lab test
preputial sample - from deeper folds of tissue where the environment is less aerobic
lamina interna - deep scrape and very cellular sample
culture or PCR
why is pyometra seen in cows with Trich?
b/c MRP occurs so CL is maintained - infection in endometrium and cervix stays closed - sets up conditions favorable for pyometra
t/f
a calf born to a cow with Trich will be weak and poorly developed
false
calf will be normal and healthy
what is special about the pouch specially designed for tissue samples for Trich testing?
designed to favor growth of anaerobic protozoa - NOT aerobic bacT
if a bull tests pos for Trich, what do you assume about his cow herd?
assume that the cows are pos too
t/f
half hearted efforts at eliminating trich from US cattle population have failed at a huge expense
true
t/f
most non preg cows become immune and free of pathogen over 5 cycles
false
3
t/f
pyometra and anestrus cause prolonged harboring of the Trich pathogen
true
t/f
pregnant cows are almost 100% clean
true
t/f
virgin heifers are 100% clean
true
what is key to control of Trich w/in a herd trying to eradicate it?
fencing
internal fencing AND perimeter fencing
keep separate populations w/in your herd separate and keep neighbors cows out of your herd
internally, what are 3 permanently separate herds a farmer should maintain if he/she is trying to eradicate trich from the cows?
- definitely clean herd = virgin heifers
- likely clean herd = cows over 60 days pregnant
- likely dirty herd = non pregnant cows that were exposed to bull
what management of bulls is important to eradicate trich from the farm?
cull all exposed bulls older then 3 yo [no test required]
retain only valuable young bulls [less than 3 yo] - test negative bulls at weekly intervals 3 times [overall, this is still risky]
DO NOT TREAT - CULL POSITIVE
how to manage 100% clean herd of virgin heifers to keep trich out?
- keep as many replacements as possible
- synch and breed by AI to CLEAN semen
- virgin herd or clean up bills
- 45 d breeding season
- test bulls at end of season to confirm clean status: if clean, add next generation of heifers and build clean herd but if dirty, start another new heifer herd
how to manage the likely clean herd to eradicate trich?
- keep bulls out until 60 d [3 cycles] after the last cow has calved
- maintain excellent nutrition to promote cycling
- synch and AI w clean semen
- use affordable or virgin herd for clean up bulls
- test bulls 30 d into breeding season: if pos, extend season and if neg, stay w short season
- 45 d breeding season
- test bulls at end of season - 3x
- cull any who do not get preg
at the end of the breeding season, if just one bull in the likely clean herd is pos, what is the next step?
cull all bulls and all non pregnant cows
how to manage the likely dirty herd of non preg cows during Trich eradication?
- cull all cows w repro dz - pyometra, mummified or macerated fetuses
- consider selling all cows in this herd
- if non pregnant cows are retained, optimize nutrition, snych and AI, young clean up bull, short breeding season, test bull after breeding, cull all non preg cows after 3 cycles
how to manage a herd living with Trich?
- cull all cows with repro dz
- use young bulls only
- extend or eliminate breeding season - allow time for initial exposure, followed by preg loss and immunity development [3 cycles] prior to end of breeding season
- vacc: eliminate pathogen from infected cows
how valuable is the Trich vaccine?
limited value
may shorten window btwn infection and self cure
but do NOT rely on vacc to cure dz - must manage herds and eradicate dz
advantages of using AI for Trich control?
- eliminates risk of venereal dz
- provides genetically superior replacement heifers
- obviates need for expensive bulls
- establishes a routine that has long term benefits
t/f
if a herd is pos, the state will impose quarantine and control
true
how does Campylobacter fetus spp venerealis compare to and differ from Trich?
- same epidemiology, pathogenesis as Trich
- abortions MC and pyometra less common (LC)
- also: vaccine controls dz 100%
what is the nature of the pathogen for campylobacter fetus spp venerealis?
anaerobic bacT
what is bovine herpes virus (IBR)?
c/s?
infectious pustuar vulvovaginitis
venereal and mechanical spread
pustules on genitalia of both sexes - 2* bacT infections common
spontaneous recovery, no long term consequences
EVA causes what reproductive issue in mares?
abortions
t/f
EVA is transmitted among mares exclusively venereally?
false
what dz of equine is no longer in the USA but causes chronic wasting and neurologic dz?
Dourine: Trypanosomum equiperdum
what strains of bacT cause endometritis?
- klebsiella
- pseudomonas
when a mare bred to one stallion has recurrent infections or if several mares w/in a herd that are bred to the same stallion have the same infection, what should you consider?
the stallion is the source of the infection
t/f
contagious equine metritis (CEM) is common in the USA
false
virtually eradicated from the USA b/c proactive horse industry did it - not b/c of laws
isolated causes of unknown origin
what does CEM cause?
endometritis and infertility as a result
where is the CEM organism harbored on the mare?
in the clitoral fossa and sinus [cavity inside the clitoris]
what kind of organism causes CEM?
mecoraerophilic organism
what is Tx / control of CEM
clitoridectomy (less often now)
clitoral stripping - incision around mucocutaneous jxn around clitoral fossa and strip mucosa - avoid erectile tissue so less bloody - sew the clitoral fossa shut around the clitoris
what condition does equine herpes virus 3 cause?
long term consequences?
equine coital exanthema - macules / papules on external genitalia
2* infections may occur
pain inhibits copulation so remove affected animals until healed
no long term consequences
what is post partum metritis?
why is it not significant?
FM ill after giving birth due to culminating infection of the uterus - common complication that occurs during the puerperium period
not significant b/c she is not bred during this time anyways so her infertility at this time does not matter
