Common Complaints in the Non-Pregnant Mare Flashcards
Contraception and undesirable behavior
• Unwanted horse issue
• Undesirable reproductive behavior in performance
mares
• Undesirable reproductive behavior in performance
mares
Estrus poor performance Cyclicity related tying up Nymphomania Aggressive behavior Male-like behavior
Causes of poor performance during estrus
Pain at ovulation (ovarian hematoma or large follicles)
May be very colicky
• Other differentials
Vaginitis
Cystitis
• Methods for elimination of estrus behavior
Progestogens Glass marbles (poor efficacy) Oxytocin injections (efficacy 70%, 45 to 50 days)
Progestins used to eliminate estrus behavior
–Altrenogest (0.044 mg/kg)
–Progesterone (0.2 mg/kg)
• Most common ovarian
tumor in the mare
Granulosa-theca Cell Tumor (GTCT)
Granulosa-theca Cell Tumor (GTCT) characteristics
• Typically benign, slow growing, non-metastatic • Affected ovary is large (8 to 30 cm in diameter) • Non-affected ovary is very small, inactive
Common complaints associated with GTCT
• Stallion-like, aggressive,
(most common)
• Anestrus
• Nymphomania
Granulosa-theca Cell Tumor (GTCT) Dx
– Transrectal palpation
– Transrectal ultrasonography
• Endocrinology
Endocrinology Dx of GTCT
• Endocrinology –Progesterone –Testosterone • >100 pg/mL – Inhibin • >0.8 ng/mL –Anti-Mullerian Hormone (AMH • > 8.0 ng/mL, diagnostic • 3.8-8 ng/mL suggestive
• Treatment of GTCT
– Ovariectomy- confirmation by
histopathology
– Normal cyclicity expected in 3 to 12
months after unilateral ovariectomy
4 classes of ovarian neoplasms
- Gonadostromal tumors
- Mesenchymal tumors
- Epithelial tumors
- Germ cell tumors
• Gonadostromal tumors
- Granulosa theca cell tumor
* Interstitial cell tumor
• Mesenchymal tumors
- Hemangioma, leiomyoma
* Germ cell tumors
• Epithelial tumors
• Cystadenoma, adenocarcinoma
• Germ cell tumors
• Dysgerminoma, teratoma
Metastases to the ovary
• Lymphosarcoma, melanoma,
adenocarcinoma
Ovarian Hematoma features
• Does not affect the estrous cycle • Regresses over a few weeks • Occasionally take several months (calcified ovary) • May cause discomfort
Common complaints in
the non-pregnant broodmare
- Anestrus
- Abnormal estrous cycles
- Repeat breeding (infertility)
- Abnormal vaginal discharge
- Abnormal external genitalia
- Mammary gland disorders
Routine examination of the reproductive organs
• Perineal conformation and examination of the vulva • Mammary gland • Palpation per rectum • Transrectal ultrasonography • Vaginal examination • Endometrial cytology and culture • Endometrial biopsy
Adavanced examination of the reproductive organs
- Endocrinology
- Hysteroscopy
- Cytogenetics
- Laparoscopy
Anestrus- causes
• Physiological: Season, puberty, PREGNANCY
• Acquired vs. Congenital
History
– Mare has shown regular cycle or has foaled before
– Mare never showed any reproductive activity
Anoestrus – Persistent CL
• Diestrus can last 60 to 90 days • Normal ovarian size, CL present (ultrasound or progesterone) • Uterus: tone (no pregnancy)
Treatment of persistent CL
PGF2α (Dinoprost thrometamine) Analogue (cloprostenol, less side effects) **** Spontaneous recovery possible
Anestrus – Persistent endometrial cups - cause
- Embryonic Death (>35 days)
- Endometrial cups already formed
- Normal genital tract on palpation
Dx of persistent endometrial cups
• eCG (commercial kits)
• Biopsy or hysteroscopy
• Check for reasons of embryonic
loss: Fibrosis, metritis, iatrogenic
Anoestrus – Ovarian tumors
Not very common • Ovarian tumors that may cause anestrus Granulosa-Theca cell tumor (GTCT) Luteoma (rare) • Need to differentiate from other causes of ovarian enlargements
Anoestrus - Pyometra
Pyometra is usually not a cause but a consequence of acyclicity CL not always present Cervical or vaginal adhesions Variable cycle history Very old mares Poor prognosis
Anoestrus – other causes
• Cytogenetic abnormalities: Ovarian dysgenesis (63 XO
Turner syndrome)
• Hormonal Treatments: Progesterone, Anabolic
steroids: negative feed back on the hypothalamus
• Nutrition: Weight loss after foaling, poor body condition
• Old mare syndrome
• Ovariectomized mares
• GnRH implants (ovuplant®) (no longer approved in the
USA)
• Immunization against GnRH (Not approved in the USA)
• Abnormal interval between ovulations causes
Aging
Anovulatory hemorrhagic follicles
Unilaterally functional ovary?
abnormal duration of estrus
Short or Split-heat (common in transitional mares)
Long estrus (NO OVARIAN FOLLICULAR CYSTS IN THE
MARE!!!)
• Abnormal duration of the luteal
Abnormal luteal function
- Failure of ovulation
- Short luteal phase
- Lengthened luteal phase
• Failure of ovulation
Anovulatory hemorrhagic follicle
Equine metabolic disease
• Short luteal phase
Early release of PGF2α from the endometrium
(endometritis, intrauterine treatment)
Abnormal corpus luteum function
• Lengthened luteal phase
Persistent CL with spontaneous recovery
Early embryonic death
Luteal insufficiency
• Not well documented • Most often suspected because of Small CL size Poor uterine tone • Treatment Progesterone supplementation – Altrenogest (0.044 mg/kg PO) – Progesterone injections (compounded)
Repeat breeding (infertility) - Hx
- Mare with regular cycles
- Review breeding management practices
- Health and reproductive history
- Previous breeding soundness examinations
- Endometrial biopsy
- Common causes of infertility
• Common causes of infertility with regular cyclicity
Fertilization failure
Early embryonic death (before day 14)
Fertilization failure
• Stallion / semen factor
• Breeding management
Gamete transport
• Breeding management resulting in fertilization failure
Technique
Gamete survival
– Timing in relationship to ovulation
– Uterine environment (endometritis)
• Gamete transport resulting in fertilization failure
Oviduct patency – Oviductal mass – Salpingitis • Cervical lesions (trauma, adhesions)
Fertilization failure - Oviductal masses
Type I collagen At the ampulla-isthmus junction Diagnosis be exclusion of all other cause Treatment- laparoscopic application of PGE2 onto the oviduct
• Other bilateral disorders of the
oviduct (uterine tube)
- Hydrosalpinx
- Salpingitis
- Ovario-bursal adhesions
Early embryonic loss (before day 14)
If the embryo dies before maternal recognition of
pregnancy. The mare will return to estrus within a
normal interval
Embryo quality
– Aged gametes
– Chromosomal abnormalities (stallion and mare)
early embryonic loss is often caused by what
decreased embryo quality, poor uterine environment (cysts, fibrosis, infection), or abnormal hormonal development (luteal insufficiency
Uterine cysts - how they affect fertility
- Reduced embryo mobility
- Abnormal placentation
- Compromised cervical tone
predisposing conditions of uterine cysts
- Factors
- Aged mares
- Origin
- Vascular changes
- Lymphatic cysts
treatment of uterine cysts
- Aspiration
* Cauterization, laser ablation
major cause of infertility in the mare
endometritis
Etiology/pathogenesis of endometritis
Contamination and establishment of infection
Failure of anatomical barriers to infection
Failure of uterine defense mechanisms
Failure of uterine defense mechanisms
– Uterine contraction (uterine clearance)
– Local immune response
– PMN function
Endometritis: Risk factors
• Age • Breed • Anatomy Perineal conformation Large pendulant uterus Endocrine disorders (Metabolic syndrome) • Endocrine disorders PPID Equine metabolic syndrome Reduced immune functio
Endometritis - Diagnosis
• Transrectal palpation and ultrasonography Large uterus Thick edematous uterus Overt uterine edema Intrauterine fluid accumulation • Vaginal examimation Cervicitis Fluid in the vagina / vaginal discharge • Endometrial cytology and culture • Biopsy (GOLD STANDARD)
Endometritis – Common isolates; bacteria
Streptococcus equi spp. zooepidemicus
E. coli
Pseudomonas aeruginosa
Klebsiella pneumoniae
Endometritis – Common isolates; fungal
(<5% of all cases) Candida spp. Aspergillus spp. Mucor spp. Others…
Endometritis – Diagnostics
Cytology, culture, bx
Endometritis - cytology
Considered positive if >2 P
endometritis - culture
Poor sensitivity in chronic endometritis
May culture one, two or even 3 bacteria
Best results is to culture from the biopsy
Endometritis - Treatment
• Intrauterine therapy • Uterine lavage (Elimination of biofilm Immunostumulation Intrauterine antimicrobials) • Systemic therapy (Antimicrobials, Anti-inflammatories) • Breeding management
Endometritis – surgical treatment
Correction of predisposing factors to ascendant infections (eg caslicks, Repair of vestibulo-vaginal sphincter)
Correction of urovagina (urethral extension)
repair of cervical tear
elecation of uterine body (uteropexy)
Repair of vestibulo-vaginal sphincter
– Episioplasty
– Perineoplasty
Uterine lavage
- Removal of intrauterine fluid and inflammatory debris
- Sterile fluids (Equine uterine flush®, LRS, 0.9% NaCl)
- 2 to 5 liters total volume
Intrauterine antibiotic infusion
Intrauterine antibiotic infusion
Endometritis – Other intrauterine treatments
• Infusion of mucolytics or chelators • Dissolve thick mucus and pus • Help to remove biofilm and improves antibiotics penetration • Infused 4 to 12 hours prior to lavage • Use of Tris-EDTA (Tricide®) • 0.6% N-acetycysteine •30% DMSO
Endometritis - Antiseptics
• 0.05% povidone-iodine in LRS • 0.5 to 2% chlorhexidine, Some mares do not tolerate antiseptic infusion
Treatment of fungal endometritis
• Correction of anatomical defects • Uterine lavage • Uterine infusion Systemic +/- topical antifungals • Candida and Aspergillus form biofilms ----Mucolytics – Tris EDTA, N-Acetylcysteine infusions
uterine infusion for fungal endometritis
• 250 ml 2% acetic acid for 3 to 4 minutes
• 2 major classes of antifungals
- Azoles (inhibit ergosterol synthesis, fungistatic)
* Polyenes (bind ergosterol, fungicidal)
Persistent Mating-induced endometritis (PMIE)
Inability of the uterus to clear
inflammatory products and semen by
12 hours post-mating or artificial
insemination
• Risk factors (Susceptible mares) - PMIE
• Uterine clearance mechanism defects
• Poor conformation
• Cervical fibrosis (Old maiden mare
syndrome)
• Treatment options
- Ecbolics (Oxytcin, PGF2α)
- Uterine lavage
- Topical therapies to relax the cervrx
- Antibiotics
- Anti-inflammatories
- Acupuncture
Treatment for PMIE: Ecbolics
• Oxytocin • 10-20 IU, IM (3 to 4 times /day starting 4 hours post AI) • Carbectocin -Long acting oxytocin analogue (not available in the USA) • Cloprostenol
Cloprostenol
• More sustained uterine contractions compared to oxytocin • Premature luteolysis if given frequently or used more than 2 days post-ovulation
Cervical relaxation
• Treatment of PMIE in “Old maiden mare syndrome” • Tight cervix • Fluid accumulation pre and post insemination
cervical relaxation - drugs
• Topical PGE1 (Misoprostol) • Crushed tablest or compounded cream • Topical Nbutylscopolammonium bromide (Buscopan®) • Compounded cream
Uterine masses/neoplasms - most common
leiomyoma
leiomyoma
• Usually solitary • Well-circumscribed • Involves myometrium • Large masses require partial hysterectomy (mares can still carry a pregnancy
Abnormalities of the external genitalia
persistent hymen
XX sex reversal
• Persistent hymen
• Perforate hymen - Incidental finding in maiden mares - Easily ruptured manually - Perforate hymen • Imperforate hymen - Accumulation of mucus in the vagina and uterus - Can bubble out of the vulva - May require surgical excision
Mastitis usually occurs when?
•Usually occurs after weaning
clinical signs of mastitis
- Clinical signs
- Swollen, warm udder
- Ventral edema
- Fever
- Hind limb lameness
Dx of mastitis
•Cytology and culture of milk •Serous, serosanguinous or purulent •S. zooepidemicus most common isolate •Ultrasonography
Tx of mastitis
- Systemic antibiotics, NSAIDs
- Frequent milking
- Hot-packing or hydrotherapy
Mammary gland neoplasia - Primary Tumors
Adenocarcinoma (MOST COMMON), adenoma
Skin origin mammary tumors
• Squamous cell carcinoma, melanoma,
sarcoids
metastatic tumors of the mammary gland
• Melanoma, mastocytoma,
lymphosarcoma
clinical signs of mammary tumors
- Mammary gland enlargement
- Pain, discharge
- Skin lesions
- Weight loss
• Diagnosis of mammary tumors
- Ultrasonography
- Cytology (FNA)
- Biopsy
metastatic pattern of mammary adenocarcinoma
• Metastasize to the inguinal lymph
nodes, liver, lungs, other organs
treatment (if no mets) of mammary adenocarcinoma
• Mastectomy • Chemotherapy • Radiation therapy • Survival < 18 months even with treatment
Inappropriate lactation in neonates
• Elevated lactogenic hormones of maternal origin in fetal circulation
• Galactorrhea
- Milk production in non-pregnant /foaling mares
- Elevated prolactin
- Pituitary Pars Intermedia Dysfunction
- Rule of mastitis
- Treatment
- Treat PPID with pergolide or cyproheptadine
- Treat others with pergolide or bromocryptine, decreased feed (protein and energy)
- Do not milk out as it will stimulate more lactation