Equine Repro Diseases Flashcards
What are clinical signs associated with Placentitis?
Ultrasound: Hyperechoic fetal fluid, placental separation, increased or decreased FHR, thickening of the uterus and placenta
Monitoring of progesterone, estrogen levels, acute phase proteins
How is placentitis treated?
Antibiotics (penicillin, gentamicin, TMS) for remainder of gestation
Anti-inflammatories (NSAIDS, pentoxyphylline)
Progesterone (altrenogest)
What is the most common cause of Rhinopneumonitis abortion
EHV1»_space;> EHV 4
What is the most prevalent viral cause of reproductive disease in horses?
Rhinopneumonitis -> Most commonly EHV1
How is EHV1 and 4 transmitted
Respiratory secretions, contact with fomites or aborted fetuses
What cells Do EHV 1 and 4 infect?
Viral multiplicaiton in lymphoid tissue –> lymphocytes carry to the rest of the body.
What clinical signs are associated with Rhinopneumonitis abortion?
Usually no clinical signs in mare preceding abortion
Death of fetus at expulsion (no autolysis) or later succumb to respiratory failure
Placenta is normal
At what point in gestation do Rhinopneumonitis aboritons occur?
typically 9th or 10th month of gestation
How is Rhinopneumonitis abortion diagnosed?
Histopathology: Necrotic foci with intranuclear inclusions in many tissues, especially liver, lung and thymus
How do you prevent Rhinopneumonitis abortions from occuring
PRegnant mares should be housed separately form other horses on the farm, and new arrivals should be quarantined prior to joining the resident population.
Vaccination: Vaccinate at 5, 7, and 9 months of gestation with EACH pregnancy
What is the only vaccine on the market that is labeled for abortion associated with Rhinopneumonitis abortions
Pneumobort K- zoetis product
What is the causative agent for Equine Coital Exanthema?
EHV-3
What are clinical signs associated with Equine Coital Exanthema
Mild respiratory disease external genitallia (both sexes)- Papules, vessicles, pustules and scabby erosions. Lesions can coalesce to larger erosions. Stallions may be reluctant to breed
What is the causative agent for Equine Viral Arteritis abortion?
Equine viral arteritis virus (EVAV)
similar to PRRS in pigs
How is EVAV transmitted?
shed in the semen of infected stallions. 1/3 become persistently infected.
How is EVAV related to abortions?
Sporadic incidence of abortion in mares typically, but abortion storms can occur
What clinical signs are associated with EVA abortion?
May be subclinical or mild infection or may have significant respiratory disease. Usually have some evidence of clinnical disease in the mares 2-6 weeks preceding abortion.
Abortion 2-6 weeks following infection (fetus appears normal)
Any time between 3 and 10 months of gestation
How is EVAV abortion diagnosed as the causative agent
Histopathology: no lesions
VI or PCR on fetal tissue is the best
Serology is not helpful unless very high titers
How is EVAV prevented?
Unvaccinated stallions should be tested immediately prior to the breeding season.
Vaccination: MLV available and required in some states
AAEP recommendation “ risk based vaccination”
Vaccinate serologically negative colts between 6-12 months of age if intended for breeding to avoid carrier state. Test serologically negative by a USDA-approved laboratory prior to initiation of vaccination.
without documentation of vaccination, serologically positive stallions are considered positive.
What are EVAV Export Regulations
Some countries forbid importation of seropositive horses unless there is documentation of serologically negative status prior to vaccination.
Vaccine- induced antibody cannot be differentiated form infection-induced antibody.
What Leptospirosis serovars are associated with Lepto abortions?
Serovars pomona and kennewicki have been mroe common in the Kentucky cases
How is Leptospirosis transmitted?
oral ingestion of urine-contaminated water.
what clinical signs are associated with Lepto abortions
Mare: fever, hemoglobinuria, icterus, renal failure and late term abortion, Equine recurrent uvitis
Fetus: emaciation, icterus, grosley abnormal liver, kidney, lungs
How is Leptospirosis diagnosed?
PCR: urine and tissue samples
FA tests with Warthin-Starry silver stain
How is leptospirosis treated?
Antibiotics: Oxytetracycline, Penicillin
How do you prevent and control cases of Leptospirosis?
Isolate infected animals- they will shed high amounts in their urine.
Vaccination- risk based vaccine recommended for pregnant mares.
Vaccinations are serovar specific!
Broad diagnostic approach to equine abotions- what samples are the best to submit
Fetus and placenta! histopath can be helpful. Culture for placentitis, PCR/VI/IHC for viral causes
General PCR diagnostic panels frequently utilized
What Foreign animal disease is associated with failure to conceive?
Contagious Equine Metritis
what is the causative agent in CEM?
taylorella equigenitalis
What disease is associated with an obligate parasite of horses that is harbored int he external genetalia of carriers
Taylorella equigenitalias, Contagious Equine Metritis
How is CEM transmitted?
Transmission either venereal via natural breeding or AI or verticle
Foals from positive mares become carriers
Fomites can transmit between stallions
Mares can resolve infections
What clinical signs are associated with CEM?
MAres: acute endometritis following breeding: copious purulent discharge, failure to conceive. Mares will either clear the infection or become chronic carriers
Stallions: no clinical signs
How is CEM diagnosed?
Culture at accreddited labs only!
Mares: vaginal discharge from clinincal cases, Swabs of the clitoral fossa and its sinuses from suspected carriers with the addition of cervical and endometrial swabs if the animal is not pregnant
Stallion: swabs are taken from the urethral fossa and sinus, distal urethra and external surface of the penis and the prepuce
PCR
how is CEM treated?
Thorough washing of the external genetalia in stallions and mares using a disinfectant soal (2% chlorhexidine)
rinsing and applicaotin of a topical antibiotic (nitrofurazone or silver sulfadiazine)
Repeat for 5 consecutive days
How is CEM prevented?
Importation: Any horse that is sexually intact and over 731 days of age orriginating form a region/country affected by CEM is subject to CEM quarantine before being allowed int o the US. Must have 2 negative semen tests while in quarantine.
What are semen export requirements for CEM?
Semen extendors must contain an antibiotic active against Taylorella equigenitalis.
Embryos need to be collected in fluid containing an antibiotic active vs. T. equigenitalis.
