Ch.43.DzesofReproductiveSystem Flashcards
During the breeding season, mares ovulate every how many days?
every 21 days
How long is estrus in the mare?
5 to 7 days
What is estrus characterized by in the mare?
-presence of ovarian follicle
-serum progesterone less than 1 ng/ml
-sexual receptivity
-cervix palpably relaxed
-uterus is edematous
When does ovulation occur?
24 to 48 hours before the end of estrus
- may be accompanied by ovarian sensitivity
The first postpartum estrus (“foal heat”) occurs in what time period after foaling?
1 week after foaling
–ovulation between 7 to 15 days
When does diestrus occur?
**luteal phase
regression of CL, caued by released of endometrial prostaglandin F2alpha (PGF2alpha) occurs 14 to 15 days after ovulation
What is the estrous cycle of cows?
ave 21 days (17 to 25 days)
What is the duration of estrus in cows?
12 to 16 hours ( range 6 to 24 hours)
In the absence of a bull, estrus can be detected in cows by:
Signs of homosexual (bisexual) activity
-restlessness
-increased activity
-vulvar hyperemia
-edema
-clear mucous discharge
When is the optimum time for insemination of cows?
between 16 to 24 hours after onset of estrus
Well managed dairy cows with uncomplicated periparturient experiences may ovulate how many days after calving?
how about in beef cows?
approx. 20 to 25 days after calving
–beef cows with nursing calves– 40 or more days after calving
Coarse wooled breeds of ewes are seasonally polyestrous in what seasons? in temperate climates
autumn and winter (short photoperiod)
Ewes of fine wooled breeds are are polyestrous in what seasons?
year round
**if adequately nourished
When does lambing typically occur in ewes, in relation to their reproductive cycle?
during anestrous season
**do not return to estrus until the next breeding season
In what seasons are goats in estrous?
polyestrous from late summer until early spring (short photoperiod)
How long is the estrous cycle in goats?
ave 21 days
**lasts 18 to 26 hours
When does ovulation occur in goats?
in 24 hours after onset of estrous
Do South American camelids bred in North America have a breeding season? and when?
Nonseasonal
– bred in a seasonal manner to avoid newborn crias born in the hottest and coldest months of year
Why do South American camelids have nonseasonal breeding season?
because they are induced ovulators
Define ovarian cysts
follicle-like ovarian structures that arise because of failure of ovulation of a dominant follicle
–persist in absence of a CL for 10 days or more
What is the mechanism of ovarian cyst development?
unknown
What is the percentage of cows that are affected by cystic follicular development?
70 to 80% of cows affected by CFD are anestrus, whereas 20 to 30% display frequent or intense estrus (nymphomania)
**affects 10 to 30% of dairy cows
Why is cystic follicular degeneration not seen in beef cattle?
b/c commercial beef cows are culled for reproductive failure
Diagnosis of cystic follicular degeneration is based on:
-accurate history
-constant or frequent estrus
-short interestrous intervals
-anestrus may suggest CFD
-clinical exam
-evaluation of ovary via rectal palpation– presence of enlarged fluid-filled structures
Ultrasonography can help differentiate cystic follicular degeneration from what other diseases
salpingitis
hydrosalpinx
oophoritis
ovarian abscesses
ovarian neoplasms
cysts of fimbria
Other causes of ovary enlargement
Clinical pathology changes in cattle with cystic follicular degeneration?
-low plasma progesterone levels (lower than cows with normal CLs)
-variable estrogen levels
What is the goal of treating cystic follicular degeneration in cows?
induces luteinization and reestablish normal etorus cycles
Spontaneous recovery from cystic follicular degeneration occurs in what percentage of cows?
up to 60% of cows that develop CFD
What are possible treatment options for cystic follicular degeneration in cows? (without spontaneous recovery
human chorionic gonadotropin (luteinizing hormone)– retrun to norm estrous cycle w/in 3 to 4 wks
Gonadotropin-Releasing Hormone (ovarian cysts), followed by luteolytic dose of prostaglandin 10 to 14 days later
Prostaglandin F2alpha (luteal cysts)
Manual rupture (thin walled follicular cysts): complications of hemorrhage with adhesion formation between ovary and system
Poor nutrition affects reproduction in what ways?
poor or weak signs of estrus
depressed ovulation
abnormal cycle
delayed puberty
What nutritional deficiencies are commonly associated with irregular estrous cycles?
energy
protein
Vitamins A and E
phosphorus
many trace minerals (iodine, copper)
Anti-Mullerian Hormone is produced by what cells? and functions in?
-granulosa cells in developing follicles
functions:
-regulation of primordial follicular recruitment and development into primary follicles, preserving the ovarian reserve
-role in folliculogenesis (unknown role)
-reliable marker for presence of granulosa cell tumors
Sheep are sensitive to the effects of phytoestrogens. What clinical observations are seen?
infertility
irregular and prolonged heat cycles
lower conception rates
early embryonic death
heat stress has what effect on reproduction?
decreases estrus detection
impair follicular development
disrupt funciton of repro tract
affect oocyte competence
lead to early embryonic death
While embryos are developing, they develop resistance to heat shock? what bovine embyro stages are unaffected by heat shock?
morulae to blastocyst stages
What are differentials for anestrus in mares?
pregnancy
prolonged diestrus
seasonal anestrus
unobserved estrus
pyometra
undernutrition
granulosa-theca cell tumor
gonadal dsygenesis
When does the mare go through puberty?
between 12 to 24 months
Transitional mares exhibit signs of estrus such as:
clitoral “winking”
tail flagging
urination in presence of stallion
Anestrous mares on rectal palpation/ultrasound
-ovaries- small and firm
-uterus-flaccid wiht a thin endomterium
-cervix with mild tone
-specumulum: caginal mucosa is pale and dry, cervox usu closed
Artificial lighting can be used in mares to move vernal transition. What typical regiment is implemented
-expose mares to 16 hours of light and 8 hours of dark by extending the photoperiod in the evening starting in late November to initiate ovulation by February
– light added toe nd of day
-or split ebetween beginning and end of teh day
What can be performed/administered to alter mares anestrus cycle?
-artificial lighting
-exposure to stallions (several times a week, ovulated sooner than not)
-Gonadotropin releasing hormone (GnRH)- induced ovulation in 2 to 3 weeks
-dopamine antagonists
-steroids
-follicular aspiration in follicles <35 mm in diameter– hasten onset of cyclicity in transitional mares
Describe pseudopregnancy
-mares embryonic lossin presence of endometrial cups (d 35 to 150 of gestation)
-condition in which a conceptus was lost after maternal recognition of pregnancy and before development of endometrial cups, resulting in prolonged luteal life
What occurs in Pseudopregnancy, despite the loss of the fetus and placental tissue, what occurs?
endometrial cups remain in palce and continue to sevrete equine chorionic gonadotropin (eCG) for similar period in pregnant mare: 100 to 150 days
What is the treatment of Pseudopegnancy?
repeated daily injections of PGF2alpha– CL older than 5 days respond to tx
What are differentials for prolonged or irregular behavioral estrus in mares?
transitional period
Granulosa-theca cell tumor
Gonadal dysgenesis
Behavioral nymphomania
Normal mare
When approached by stallion what is normal estrus behavior in mare?
-ears held forward
-elevate tail
-rhythmically evert the clitoris (“winking”)
-assume squating posture
-urinate
-lean against teasing chute toward stallion
When approached by stallion, what is normal diestrus behavior in a mare?
hold ears back
strike, kick, squeal, swish tails and forcefully void small amount of urine
Behavioral nymphomania or abnormal estrous behavior and aggression may be seen in mares when?
at any stage of estrous cycle
**ovarian tumours considered an important differential
What are differential diagnosis of anestrus in cows?
Pregnancy
unobserved estrus
cystic follicular degeneration
pyometra
mummified
fetus
undernutrition
granulosa theca cel tumor
freemartinism
ovarian hypolasia
Dairy herds in which infertility is caused by inaccurate estrus detection are usually characterized by:
-prolonged intervals from calving to first breeding and between services
-insemination intervals of 10 to 15 days and 30 to 25 days
-records of examinations that confirm cyclic ovarian changes but in which observation of estrus is not recorded
-finding more than 15% cows presented for pregnancy examination to be nonpregnant
What is the treatment of the silent estrus in cattle? and what are the limitations?
PGF2alpha
-inaccurate palpation of the temporary ovarian structures
-injection during the wrong phase of the cycle
-failure of manager to observe estrus in treated cows (timed AI can be used to overcome this problem)
Sexual differentiation occurs in what three stages?
each stage is dependent on the previous one
- Chromosomal sex
- Gonadal sex
- Phenotypic sex
When is chromosomal sex determined?
at fertilization in mammals by the type of sex chromosome contributed by the sperm (X or Y). In mammals, females are XX and males XY
Gonadal sex is regulated by what gene?
Sry (sex determining region of the Y chromosome gene– produces a protein called the HY antigen
activation of this pathway induces testis formation in the bipotential gonads and X-linked Dax1 gene suppresses testis formation
What is phenotypic sex regulated by?
substances produced in the male testes to cause regression of the female tract and formation of the male tract
or, in the absence of a testis, formation of the female tract
abnormalities in chromosomal sex occurs because of:
nondisjunctional errors during either mitosis or meiosis
Monosomy X is known as what syndrome and is due to what genetic abnormalities?
Turner syndrome
lack of a Y chromosome and consequent Sry genethe phenotype is female
What is the most common reported chromosomal abnormalities in mares
Monosomy X
(turner syndrome)
Mares with monosomy X (Turners syndrome) have what characteristic C/S
-history of poor performance
-lack of or sporadic repro cyclicity
-ovaries small, inactive, smooth and firm
-uterus and cervix- usu hypoplastic
-externally mares genitalia may appear normal or underdeveloped
XXY Syndrome is part of Klinefelter syndrome because of what genetic abnormality?
presence of a Y chromosome and the consequent Sry gene, phenotypically male– generally have hypoplastic genitalia and repro organs
factor on X chromosome must escape the inactivation process, which happens early in development
What clinical signs are seen with the XXY syndrome?
testicular development and spermatogenesis are inhibited–> small, flaccid testes and azoospermia
+/- retained/descended testes
-normal libido & sexual behavior
+/-low testosterone concentrations
**infertility always accompanies this syndrome
What is seen with XXX genetic makeup?
report of an infertile mare– bilat small, inactive ovaries and a hypoplastic uterus and cevix
Define mosaics genetically
individuals that have at least two cell lines with different karyotypes arising from the same zygote
Define true hermaphrodites
mosaics that have mixed gonadal dysgenesis, with an ovary and a testis, or ovotestes, owing to sex chromosome mosaic cell lines
Define chimeras
individuals having cell lines from two different embryonic sources
Cause of chimeras?
-natural fusion of blastocysts in utero
-suspected double ovulation and fertilization followed by blastomere fusion (suspect in a horse)
What is the effect of chimerism seen in ruminants?
freemartinism– resulting in chimeric twins
Define freemartinism
phenomenon in ruminants in which an infertile female is twin to a male
What abnormal development results in freemartins?
-dizygotic occurrence happens when the blastodermic vesicles of 2 zygotes fuse early in development (cattle: d 18 to 20) and share embryonic tissue
-placentas fuse (day 30 to 50) and share blood through gestation
**occurs before gonadal differentiation at day 40 to 50
What is the genetic makeup of a freemartin?
XX/XY– both individuals
What are the effects of freemartinism in the female?
-lacks a cervix, uterus, uterine tubules and cranial vagina
-vulva is normal
-yearling free martin fails to exhibit estrus, udder and teats remain small and free martin externally resembles a steer (only with a vulva)
How can clinical diagnosis of free martinism be made?
-establish a blind end to the vagina (no cranial vagina, no cervix)
-confirm with genotyping or use of PCR to detect Y chromosome in a phenotypic female
what number of fetuses are seen with ovine free martinism?
-rare with twins or triplets
-common quadruplets or quintuplets
What genes act downstream of Sry to support gonadal differentiation?
Sox9
Gata4
Wt1
Sf1
synergistically promote testicular differentiation
When do sex reversals occur?
When chromosomal and gonadal sex do not agree with each other
ie: XX: sex reversed males, XY sex reversed females or true hermaphrodites (both ovarian and testicular tissue on separate gonads)
What cells secrete testosterone?
Leydig cells
What two steroids promote the differentiation of male genitalia?
Testosterone
dihydrotestosterone
The tissues that form the round ligament of the uterus are analogous to what male body part?
the male gubernaculum
Abnormalities of phenotypic sex occur because of:
when chromosomal and gonadal sex agree (XX with ovaries and XY with testes), but the xxternal and/or internal genitalia do not correlate or are amibiguous
**male or female pseudohermaphrodites
What are the most common causes of bilaterally small ovaries in the mare?
- seasonal anestrus
- Hypothalamopituitary dysfunction
- severe malnutrition
- Immaturity
- Advanced age
- Use of anabolic ssteroids
- gonadal dysgenesis
What is the affect of anabolic steroid administration in mares reproductively?
-Suppression of gonadotropin secretion
-effect on both estrous behavior and ovarian size and function
-low doses (aggressive or stallion-like behavior)
-high doses (inhibit ovarian activity, failure of follicular development & ovulation)
Mares with gonadal dysgenesis result in what characteristics of the reproductive tract?
-ovaries are small, firm, smooth & inactive
-tubular tract thin and flaccid
-endometrial hypoplasia
-mares are sterile & NO TX
What is the effect of PPID on the equine productive cycle?
-abnormal estrous cycles
-infertility
-possibly both
PPID causing decreased fertility is due to?
unknown mechanisms
-destruction of gonadotrophs of anterior pituitary
-insulin resistance– suspect role in ovarian steroidogenesis & follicular development
PPID mares that are pregnant, what is important to remember about their treatment with pergolide?
D/C 30 days before expected foaling until 1 month postpartum and mares should be monitored for decreased milk production
What are the most common causes of enlarged ovaries in the mare?
- tumors
- anovulatory follicles
- ovarian hematomas
- pregnancy
Most equine ovarian tumors are categorized as:
- sex cordstromal tumors (granulosa-theca cell tumors)
- epithelial tumors (cystadenomas)
- germ cell tumors (dysgerminomas and teratomas)
What is the most common ovarian tumor in the mare?
Granulosa- theca cell tumor (GCT)
Granulosa theca cell tumors develop from what cells?
steroidogenic cells of the follical- resultin gin abnormal secretion of inhibin and testosterone
What are characteristics on ultrasound of the reproductive tract of a mare with granulosa theca cell tumors?
-affected ovary: multi-cystic or honeycombed structure, solid mass or single larger cyst
-contralateral ovary: small & inactive
Granulosa theca cell tumors are hormonally active, what clinical diagnostic assay can be used for the detection of GCT tumors?
alpha inhibin: INC in 90% of mares with GCT
serum testosterone: elevated in 50 to 60% of affected mares
Progesterone: always below 1 ng/mL, b/c normal follicular development, ovulation and CL formation does not occur
Antimullarian hormone: GCTs consistently higher than normal cyclic & pregnant mares– excellent tool in dx of GCT
Granulosa theca cell tumors: clinical signs
-enlarged clitoris
-INC mm mass
-crested neck
other C/S: colic, lameness and weight loss
Granulosa theca cell tumors: treatment
Surgical removal:
-colpotomy
-flank and ventral midline laparotomy
-laparoscopy
What is the most common tumor of the surface of epithelium of the equine ovary?
cystadenoma
what are equine ovarian cystadenomas?
rare, benign
hormonally inactive tumors from surface of epithelium of the ovulation fossa
-tumor unilateral
-contralateral ovary is normal
Treatment of cystadenomas in the mare?
Benign tumors
– usu surgically removed
What are ovarian tumors of germ cell origin?
dysgerminomas and teratomas– rare ovarian tumors
**both tumors are unilateral & hormonally inactive
What are Dysgerminomas?
germ cell tumors
-affected ovary unilaterally enalrged & multicystic
-malignant
-often metastasize to peritoneal and thoracic cavity
What are ovarian teratomas?
arise from 3 germinal layers
-neoplastic ovary may contain bone, cartilage, teeth, hair, muscle and nerves
Ovarian teratomas effect reproductively?
Do not cause C/S, interrupt the estrous cycle or alter the behavior of the mare
Treatment of germ cell tumors (teratomas vs dysgerminomas)?
Sx removal for both
What is the prognosis for germ cell tumors (teratomas vs dysgerminomas)?
teratomas: good
dysgerminomas: poor
Persistent anovulatory follicles result in what reproductive alterations?
-abnormal estrous behavior
-prolonged interovulatory intervals
What is the treatment of anovulatory follicles in mares?
hCG or GnRH agonist to induce ovulation or luteinization of the anovulatory follicle – gen not effective
prostaglandins result ind estruction fo luteal cells in mares with luteinized PAFs
Most nonluteinized persistent anovulatory follicles spontaneously regress in what time period?
1 to 4 weeks
Ovarian hematomas develop when?
hemorrhage into follicular cavity is normal during ovulation
–occasionally hemorrhage is severe, resulting in formation of an ovarian hematoma that may be 10 cm in diameter or larger
What is the effect of ovarian hematomas on the reproductive cycle of mares?
No effect
**careful to not mistake for GCT
What should be considered when mares exhibit stallion-like behavior, elevated serum testosterone concen and enlarged ovaries?
pregnancy– pregnant mares show stallion like behavior d/t testosterone production
Multiple secondary CLs form in pregnant mares at 40 to 180 days of gestation– bilaterally enlarged ovaries
When does the CL usually regress?
14 to 15 days after ovulation
When does the CL regress with PG2alpha administration?
Until 5 days after ovulation
Embryonic loss after maternal recognition of the fetus can result in a persistent CL for what period of time?
35 to 90 days
Why does the equine conceptus produce a PGF2alpha inhibitor factor 11 to 13 days after ovulation?
Factor prevents PGF2alpha from being synthesized and secreted by the endometrium
–> result in a prolonged luteal phase of the primary CL until the development of endometrial cups and secretion of eCG ensure the presence of functional luteal tissue in the pregnant mare
What are potential causes of persistent corpus luteum?
- normal equine conceptus secretion (11 to 13 days post ovulation)
- embyronic loss after the time of maternal recognition
- destruction of endometrium in infectious and inflammatory conditions
- late diestrous ovulation (CL insufficiently mature to respond ot endogenous PGF2alpha release
- Nonsteroidal anti-inflammatory drugs may inhibit endometrial PGF2alpha synthesis
- Repeated tx with oxytocin before upregulation of oxytocin receptors occurs (before day 13) has resulted in a prolonged luteal phase
- Spontaneous CL persistence (controversial)
A persistent CL may be suspected in what mares?
-not expressing normal estrous behavior during the physiologic breeding season
**differentiate from mares in silent heat
Progesterone concentrations greater than what level are indicative of the presence of active luteal tissue?
> 1 ng/mL
Treatment for persistent corpus luteam
**after pregnancy has been ruled out with U/S
–luteolysis can be achieved with administration of 5 to 10 mg of alpha progstaglanding product dinoprost tromethamine or similar prostaglandin analog
**must be 5 days post ovulation to respond appropriately
What is the most common cause of premature luteolysis in the mare? (<15 days)
endometritis
Primary luteal insufficiency implies what?
a deficiency in progesterone production
Why does endometritis result in premature luteolysis?
Inflammation– result in an acute activation of inflammatory mediators (including PGF2alpha)
–> inflammatory effect of PGF1alpha and may cause luteolysis and return to estrus
Luteal insufficiency besides lack of progesterone production, what other condition can cause luteal insufficiency?
With endotoxemia
**mares with gram negative infection
What is the minimum amount of progesterone required to maintain a pregnancy?
2 ng/mL
Diagnosis of luteal insuffiency?
repeated samples of progesterone b/c prostaglandin is released episodically
What is the treatment for luteal insufficiency?
Supplementation with progesterogen altrenogest at dose of 0.044 mg/kg PO q24 h
When can treatment with altrenogest be discontinued?
at 80 to 120 days of pregnancy or longer, and measurement of endogenous progesterone level greater than 2 ng/mL
Can a mare be on altrenogest, when a sample to measure progesterone is taken?
yes– progesterone and altrenogest do not cross-react on radioimmunoassay (RIA)
Why is it important to know when to discontinue altrenogest administration?
a case of mummification of a 5 month old fetus in a pregnant mare at term has been reported
**mare was maintained on altrenogest throughout gestation
Does spontaneous prolongation of luteal function in the presence of a normal, nongravid uterus occur in cows?
No
What mechanisms in cows cause suspected luteolytic mechanism? resulting in prolonged luteal function, persistently elevated progesterone concentrations and anestrus.
Common causes:
pregnancy
pyometra
mummified fetus
segmental aplasia (including uterus unicornis)
On transrectal palpation what are signs of pregnancy in a cow?
fetal membrane slip
amnionic vesicle
placentomes
fetus
Pyometra is characterized by:
accumulation of variable amount of mucopurulent exudate within the uterine lumen, failure of luteolysis and subsequent anestrus
What medications can be given to a cow to abort a fetus/mummified/pyometra?
D7-150 of gestation: PGF2alphaproducts (dinoprost tromethamine or cloprostenol)
**same with mummified fetus and pyometra
> 150 days: PGF2alpha and dexamethasone
Ovarian hypoplasia occurs as an inherited trait in cattle, through what mode of inheritance?
autosomal recessive trait in cows
**complete penetrance
What is the most common ovarian neoplasia in cows? (rare)
granulosa cell tumors
What is the best diagnostic test for granulosa cell tumors in cattle?
AMH
–inhibin is not validated for cattle
–estrogen and testosterone are variable
What are other causes, besides granulosa cell tumors, of ovarian enlargement in cattle?
other ovarian neoplasias (dysgerminomas, interstitial cell tumors, teratomas)
ovarian cysts
oophoritis
ovarian abscesses
parovarian cysts
What is the treatment of ovarian neoplasia in cattle?
surgical removal– cows may not be as fertile as mares after removal of a tumor
Ovulation tags in cattle develop when?
after ovulation, resulting from blood loss associated with rupture of the follicle
Do ovulation tags in cattle affect fertility?
Usually no
Severe ovarian hemorrhage may cause adhesions between ovary and burs, interfering with their normal function
What are causes of oophoritis in cattle?
-traumatic manipulations
– enucleation of CLS and attempts to drain fluid form ovarian cysts
-ascending infections from the uterus
- may accompany brucellosis, mycoplasmosis and tuberculosis
Define salpingitis
inflammation of the oviducts is characterized by macroscopic enlargement
Necrotizing and granulomatous salpingitis may follow infection with what bacteria?
Trueperella pyogenes
Mycocaterium tuberculosis
Brucella abortus
Salpingitis may be caused by:
-manipulations of the ovaries & uterine tubes by palpation per rectum
-transvaginal ovum pickup
-aggressive irrigation of an infected uterus
-inappropriate treatment with estrogenic hormones
What is Pyosalpinx characterized by?
-segmental accumulation of pus within the lumen of the oviduct after mechanical blockage of either end
-frequently follows severe cases of uterine infection & may be complicated by perimetritis and localized peritonitis
Hydrosalpinx is characterized by:
accumulation of thin mucous within the lumen of the oviduct
What are common sequelae to chronic salpingitis?
-Hydrosalpinx
-adhesions to perisalpingial tissues
What kind of placenta dose the mare have?
epitheliochorial placenta– characterized by diffuse microvilli that interdigitate with endometrial crypts
What is the most common site of partial retained fetal membranes?
Previously nongravid horn
What are potential sequelae to retained fetal membranes?
tetanus
metritis
endometrial fibrosis
invagination of uterine horn
uterine prolapse
laminitis
What kind of placenta to cattle have?
cotyledonary
When is a placenta considered retained in cattle?
> 12 hours
What is the reported prevalence of retained fetal membranes in dairy cattle?
8 to 12 %
What are causes of retained fetal membranes in cattle?
failure of fetal cotyledons to separate from crypts of maternal caruncles
Besides mechanical the factors (ie strong myometrial contractions) associated with expulsion of the placenta in cattle, what else contributes to the expulsion of the placenta?
INC collagenase– in response to increasing relaxin and estrogen prior to parturition, which promotes collagen breakdown at the cotyledon-caruncle interface
In Cattle, what factors are associated with retained fetal membranes?
-induced parturition
-abortion
-dystocia
-cesarean section
-twinning
-nutritional deficiencies (selenium, vitamin E, Vitamin A)
the precise reason is unknown
What percentage of cattle develop metritis with retained fetal membranes?
20 to 25%
The majority of cows with retained fetal membranes have no serious clinical signs, other than what:
decreased milk production and appetite
What are treatment options for cattle with retained fetal membranes:
- manual removal-contraindicated if patient is septicemic
- myometrial stimulants- oxytocin, IV calcium in hypocalcemia cases (may not be super beneficial)
- prostaglandin: questionable efficacy
4.Antibiotics: indicated when cow has fever, off feed or drop in milk production - collagenase: not economical, intrauterine not beneficial
Trauma caused by manual removal of a cows placenta causes what?
Inhibits phagocytosis by uterine neutrophils and predisposes to severe sequelae, including endometritis, septic metritis, peritonitis and delay to first ovulation
When are fetal membranes considered retained in ewes and does?
> 12 hours
What are other tissues in ewes and does, besides the placenta, that may be seen:
prolapsed uterus
prolapsed or everted urinary bladder
prolapse of some portion of the digestive tract through a uterine rupture
prolapsed rectum
prolapsed vagina
twin fetus
In camelids when is the placenta usually passed?
within 1 to 2 hours of parturition
What kind of placenta do camelids have?
diffuse, microcotyledonary, epitheliochorial
**sim to horses
**exception that left horn is almost always the pregnant horn
In mares, persistent endometritis can be divided in to what categories based on pathogenesis?
- sexually transmitted diseases
- persistent uterine infection
- persistent breeding induced endometritis
What is an example of sexually transmitted disease in mares that may cause persistent endometritis?
Taylorella equigenitalis– contagenous equine metritis (CEM)
What bacteria are most commonly isolated in mares with persistent uterine infection?
Beta hemolytic streptococci (strep zoo and Strep equisimilis)
E coli
Pseudomonas aeruginosa
Klebsiella pneumoniae
Breeding naturally causes a level of endometritis in mares, what is the mechanism by which the uterus removes sperm?
-compliment cascade/inflammatory response
-increased myometrial contraction in response to breeding
-other mech: PMB-phagocytosis of spermatozoa
In regards to breeding associated endometritis in mares, if inflammation persists beyond what days can embryonic loss occur?
persistent inflammation when the embryo enters the uterus at 5 days after ovulation
Spermatozoa have an inflammatory effect on the uterus, what has a suppressive effect on complement activation, PMN chemotaxis and phagocytosis?
Seminal plasma
When taking samples for uterine culture (mare), in what part of the cycle should this be performed?
During estrous
What is the most accurate method to diagnose persistent infectious endometritis?
culture and histo interpretation of an edometrial biopsy
Characteristics of chronic endometritis on uterine biopsy:
-infiltration of endometrium with mononuclear cells
-deposition of layers of fibrosis around endometrial glands
The spread of contagious equine metritis on ednemic farms is best prevented by:
-strict hygiene
-screening of breeding stallions before breeding season
-use of AI
Treatment of persistent uterine infections in mares consists of:
1.removal of all potential sources of contamination
2. Antibiotic administration: local or systemic routes
3. Other treatment options: N-acetylcysteine, EDTA, cationic steroid antimicrobial, Hydrogen peroxide, bActivate
4. immune modulators; bacterial cell wall extracts, plasma, corticosteroids, NASAIDs, Lactoferrin
5. uterine lavage post breeding
6. ecbolics: oxytocin, carbetocin, prostaglandin,social interaction with a stallion
7. electroacupuncture
When is the earliest a uterine lavage can be performed in a mare post insemination (AI)?
Sperm transport to the oviduct is completed within 4 hours after breeding, uterine lavage 6 to 24 hours after breeding will not have a negative effect on breeding
What is the prognosis of pyometra in mares?
Normal fertility: guarded to poor
–> b/c the development of pyometra in mares (cervical stenosis and adhesions) difficult to tx and b/c severe endometrial destruction may develop
In Cattle:
Lochia is normally expelled during what time period?
2 weeks after calving: range from dk red or brown to white to clear
-may continue until 30 days after calving
What antibiotics are commonly used in the treatment of Bovine metritis?
Oxytetracycline
Penicillin
Ceftiofur
Postcoital pyometra may be caused by what organism in natural breeding dairy and beef herd?
T. foetus
Define perimetritis
characterized by inflammation of the peritoneal surface of the uterus and may be accompanied by localized or diffuse peritonitis
**adhesions between the uterus and other pelvic and abdominal organs
Perimetritis can occur in all species as a sequela to:
severe uterine infections
uterine rupture
penetration of the vagina during mating
traumatic insemination or obstetric procedures
Cesarean section
Perimetritis differential diagnosis in cows
traumatic reticuloperitonitis
displacements of parts of the digestive tract
abomasal ulcers
postpartum metritis
abdominal fat necrosis
In ewes, what infectious causes is a cause of retained fetal membranes and metritis?
Listeria monocytogenes
Campylobacter spp
Chlamydophila abortus
What is the most important factor causes damage to and contamination of the uterus in camelids?
-unnecessary mating or overbreeding (most important)
Others:
-retained fetal membranes
-rectal vaginal tears
-unsanitary obstetric manipulations
Chronic endometritis in camelids will often not cause evident clinical signs, but acute postpartum endometritis may cause signs of:
fever
depression
signs of shock
Treatment of endometritis in camelids
**similar to the mare
What are anatomic defects in camelids that are associated with genital infections?
*pneumovagina
–other defects: urovagina and perineal lacerations
endometrial cysts and lymphatic lacunae develop from what in mares?
–common degenerative changes of the endometrium that are prevalent in mares older than 11 years of age than in younger mares
What are the possible treatments for endometrial cysts and what would be the indications for surgery?
**do not req treatment unless they are suspected to interfere with pregnancy (large & numerous)
Tx options:
-endoscopic guided laser surgery
-electrocoagulation
-needle aspiration
-mechanical rupture of the cyst
-uterine curettage
-intrauterine infusion o fhypertonic saline solution
What is important in the uterine prolapse in preventing its recurrence?
correct positioning
What is the prognosis for uterine prolapse in the mare?
-related to development of sequelae, such as:
- uterine tears
- metritis
-endometrial damage
In cows, uterine prolapse is most often associated with what?
hypocalcemia–> lack of uterine tone and delayed cervical involution
What are predisposing factors for uterine prolapse in does?
dystocia
hypocalcemia
lack of exercise
For an elective uterine prolapse in a cow (to repair a uterine tear), what can be administered
epinephrine (10 ml, 1: 1000) diluted in 250 ml sterile saline and administered IV slowly
–epidural administered immediately after the uterine tissue is everted
Do leiomyomas of the uterus affect fertility?
-benign
-arise from outer smooth muscle of the uterus without need for a preparatory event
**not necessarily assoc with repro failure. Fetus and tumor can co-exist
Tumors of the uterus (however rare) should be differentiated from:
normal fetuses
mummified or macerated fetuses
placentomes
abscesses
fat necrosis
What is segmental aplasia in cattle?
“white heifer disease”
– cranial parts of the genital tract are normal and endometrial secretions from the parts of the uterine horns accumulate b/c normal drainage of the cervix is impeded
–various defects: nearly complete absence of tubular genital organs to an imperforate hymen that blacks secretion drainage
An imperforate hymen in cattle may be confused with what other differentials?
**tissue may bulge from vulvar cleft:
- vaginal prolapse
-prolapse or eversion of the urinary bladder
-cystic vestibular glands
-neoplasia of the vulva or vagina
What is the treatment for segmental aplasia in cattle?
only tx is for imperforate hymen– that occludes an otherwise normal tract, incision followed by drainage of accumulated secretions
What is uterus unicornis?
aplasia of one paramesonephric duct that leads to the development of one uterine horn
**seen in cattle, rare
Uterus didelphis occurs when?
When caudal parts of the paramesonephric ducts do not fuse, when the cervix and uterine body are completely duplicated
Does uterus didelphis affect fertility?
affected animals may conceive through cervix and uterine horn ipsilateral to ovary about to ovulate
**affected animals may be unable to carry pregnancy to term b/c of lack of placental attachment in the nongravid horn
Hydrometra or Pseudopregnancy in small ruminants is characterized by:
-accumulation of several liters of clear fluid within the uterus
-abdominal distention
-persistence of a CL
-anestrus
What is a cloudburst in small ruminants?
spontaneous correction of hydrometra– expulsion of accumulated fluid approx. 150 days after an infertile mating (w/o fetus or placenta)
Treatment of Pseudopregnancy/hydrometra in small ruminants?
Prostaglandin (Lutalyse or extrumate)
The prevalence of hydrometra is highest in what population?
-increased in herd where breeding is delayed in order to obtain winter milk
-does manipulated hormonally to breed out of season
What are common cause of pyometra in the mare?
endometritis
cervical adhesions
What are causes of pneumonovagina in mares?
secondary to changes in perineal conformation, including:
-cranioventral displacemnt of repro tract
-loss of integrity of vestibulovaginal sphincter
-loss of integrity of the vulvar labia
**common in older multiparous mares
What surgical procedures are available to prevent the anterior flow of urine?
-urethral extension
-vaginoplasty
What is the causative agent in ifnectious pustular vulvovaginitis in cattle?
bovine herpesvirus 1
**different strain genetically from BHV-1 cause of infectious bovine rhinotracheitis
Do BHV-1 respiratory and genital forms coincide with abortions?
No– abortions are not seen with genital form of dz
Spread of infectious pustular vulvovaginitis (BHV-1):
coitus
mechanical means
infectious pustular vulvovaginitis (BHV-1) incubation period
1 to 3 days
What clinical signs are seen with genital form of BHV-1?
-mucopurulent vaginal discharge
inflamm of vaginal and vulva mucosa
-pustules develop over lymphoid follicles and progress from small ulcers to coalescing erosions
-inflamm of penis & prepuce (painful)
reluctant to mate
What is the treatment for the genital form of BHV-1?
Not required, will resolve in 10 to 30 days
Clinical signs of vaginal varicose veins in the mares?
no signs to persistent and profuse vaginal hemorrahge
**typically older mares
Vaginal varicose veins should be differentiated from what in mares?
vaginal trauma
premature separation of the placenta in periparturient mares
Etx agent of the equine coital exanthema?
EHV-3
Clinical signs of equine coital exanthema
-mild and transient, recurrent
-lesions: Mares: vulva, perineum; Stallions: penis & prepuce
–>small papules that progress to pustules and then ulcers (rarely see lesions ion conjunctiva, lilps, nares and mucosa of upper resp tract)
Histo of equine coital exanthema lesions
intra-nuclear inclusion bodies apparent in epithelial cells
**histo sections from active edge of ulcers
Treatment required for equine coital exanthema?
lesions heal spontaneouslyw/in 14 days–> leaving depigmented spots
Disease characteristics of Granular vulvitis
**seen in all spp, esp cattle
development of granules or papules in the vulva mucosa accompanied by genital discharge
+/- infertility
Ulcerative dermatosis in small ruminants- describe the disease
venereal disease of sheep caused by parapoxivirus similar to but distinct from virus that causes contagious ecthyma
C/S of the ulceration of the skin & mm of vulva of ewes and penis prepuce of rams (also on lips, nares, feet and elgs), lesions are painful
Treatment of ulcerative dermatosis genital lesions in sheep:
lesions usually resolve in 7 to 10 days
–symptomatic tx with local astringent and antiseptic oitnments
What is the most common anatomic defect of the vulva of mares and cows?
abnormal labial approximation–> leading to pneumovagina and subsequent to infertility
-traumatic incident or imperfect conformation
Causes of clitoral hypertrophy:
-intersex conditions
-fillys whose dams received progestins during pregnancy
-admin of anabolic steroids
-cows assoc with free martinism
What is the most common neoplasia of the labia of mares and what should they be differentiated from?
melanomas & SCCs
DDx: habronemiasis, granulation tissue, sarcoids
What are the most common tumors affecting the vulva of cattle?
viral fibropapillomas
Ectopic mammary tissue has been described in what large animal spp and in what location?
does
– swelling of the vulvar lips– enlargement begins before each parturition and persists for approx 2 months
- benign unless interferes with evacuation of feces or urine
What are the major infectious causes of abortion in mares?
-EHV-1
-equine viral arteritis (pestivirus)
-Nocardioform actinomycetes (crossiella equi, Amycolatopsis spp)
-Strep zooepidemicus
-Mycotic abortion (Aspergillus and other spp)
-Leptospirosis
what percentage of thoroughbreds have a double ovulation?
20 to 30%
With treatment of twins, when can an embryo be manually crushed?
less than 16 days of pregnancy
**when embryos are typically fixed at this site after day 16- 20. After day 20 risk crushing both embryos
After manual crushing of one twin embryo in mares, what is the survival rate for the remaining embryo?
greater than 90% when twin reduction is performed before day 20
What treatment options are available for the abortion of a twin pregnancy after day 16 (when manual crushing is not an option)?
Benign neglect- most will resorb one twin, while other persists
Day 37 to 38: formation of endometrial cups- refer mare for advanced, selective twin reduction: transvaginal, U/S guided fetal aspiration, transcutaneous, U/S guided fetal intracardiac injection or PPG or KCL or craniocervical dislocation
A diagnosis of abortion d/t umbilical cord torsion can only be made when?
localized swelling and discoloration accompany the twisting
What is the leading cause of equine late-term pregnancy loss in the United States?
Placentitis
What organisms are most commonly cultured from aborted fetuses:
Strep spp
E coli
Pseudomonas
Klebsiella spp
Staph spp
Leptospira spp
What are the most common reported mycotic abortions in mares?
Aspergillus fumigatus and Mucor spp
What is the pathogenesis of placentitis?
most common: ascending via the cervix–> loss of chorionic villis around cervical star
- allatochorion lesions may include: nodular cystic allantoic masses, edema, necrotic areas of chorion, necrotic mucoid exudate coating the chorion
Hematogenous cause of placentitis shows what different lesions?
generalized, diffuse loss of villi
Mares with nocardioform placentitis show what lesions
-loss of chorionic microvilli
- covered by brownish, thick and tenacious exudate in focal area around ventral aspect of the uterine body and base of the uterine horns
Pathogenesis of nocardioform placentitis?
unknown
-b/c bacteria & inflamm limited to interface between chorion and endometrium, abortion postulated d/t nutritional deprivaiton fo teh fetus resulting from separation between chorion and endometrium
What are common C/S of pending abortion caused by ascending placentitis?
udder development
vaginal discharge
What changes are seen on U/S that indicate placentitis?
-hyperechoic fetal fluids
-placental separation
-inc or dec fetal heart rates (norm range 75+/- 7bpm)
-thickening of combined thickness of uterus and placenta (CTUP)
-edema of allantochorion
-separation of endometrium
Where is the CTUP measurement made?
1-2 inches cranial to the cervicalplacental junction– then moved laterally until a major uterine vessel is visible at ventral aspect of the uterine body
–Measure CTUP between vessel and allantoic fluid (important to get CTUP measurements from the ventral aspect of the uterine body)
What is seen grossly on the placenta with placentitis?
thickened and leathery in cases of mycotic placentitis, with lesions demarcated from rest of chorionic surface
- affected areas is edematous, thickened and discolored or brown with a mucoid or fibrinonecrotic exudate on the surface
- ascending placentitis lesions– are most severe on the chorionic surface at the area opposite from cervix to the body of the placenta
What functions in maintaining pregnancy after the endometrial cups and secondary corpora lutea disappear at days 120 to 150 of getation?
the placenta
Can 5 alpha pregnanes be used to determine placental pathology as a diagnostic for placentitis?
No- not commercially available (has been shown to be increased in mares with placentitis)
Is measuring estrogen levels diagnostic for placentitis?
- serum estrogen concentrations BELOW normaly detected in pregnant mares
When is relaxin produced and by what part of the fetal-placental unit?
equine placenta
-measured in plasma from day 80 of gestation throughout pregnancy
-role is not well understood
Does serum amyloid A increase wiht placentitis?
experimentally induced placentitis- SAA values increased
Placentitis treatment
- combat infection: broad spectrum antimicrobials
- reduce inflammation: NSAIDs
- controlling myometrial activity: Altrenogest
