Exam 2 Flashcards
What are the most common reasons for ovarioectomy in the mare?
Behavioral issues
Due to:
-tumors (granulosa cell tumors, theca cell tumors)
-hormone responsive behavior changes secondary to estrus cycle
-to make mare a tease mare
List approaches to gonadectomy in mares
Open methods:
Colpotomy
Laparotomy
Ventral midline celiotomy
Oblique paramedian celiotomy
Less invasive:
-Flank laparaoscopy
Why do we typically just remove the ovaries in mares?
Short broad ligament in mares makes it hard to take entire uterus out
List pros of and cons of a colpotomy in a mare
Pros:
- cheap
Cons:
-many post-op complications (hemorrhage, evisceration, fecalectomy)
-it’s a blind procedure
What is a colpotomy in a mare?
Surgical incision into the wall of the vagina
Blind procedure where you crush pedicles with chain of ecrasure; you cause hemostasis as you crush pedicle
good option for commercial or jump mares
What are the pros and cons of a ventral midline celiotomy approach for ovarioectomy in a mare?
Pros: helps for removal of tumors >20 cm in diameter
Cons: more invasive
What are the pros and cons of flank laparoscopic ovariectomy in a mare?
Pros: small incisions, not blind because you have a scope , minimal recovery time
Cons:
-post op colic
-can only removal normal sized ovaries + small tumors
What is the most common reason to perform a partial hysterectomy in a mare?
Presence of a tumor!
Usually a leiomyoma = most common tumor of uterine wall in mares
Done to restore fertility; masses interfere with normal uterine clearance and promote endometritis
What is the most common cause of pyometra in a mare?
Fibrosed cervix that is closed or partially open
= cervix unable to clear something
Very rare for horses to get a pyo and very rare to perform an OVH on them
What are some castration techniques used in large animals?
Banding —-> place band around scrotal tissue
Crimping: crush spermatic cord
Surgical castration : open scrotum and remove testicles
What is an important complication that can result for banding castration?
Tetanus
What is a major complication that occur from making a scrotal incision to castrate a large animal?
Hemorrhage!
What is the most important thing to remember if you are using a Serra emasculator to castrate a large animal?
Nut to nut orientation or else hemorrhage will occur!
Nut of emasculator should be oriented towards the testicle
The emasculator crushes proximally, and cuts distally (DO NOT REVERSE OR HEMORRHAGE WILL OCCUR!)
What will twin pregnancy result in with horses?
-spontaneous reduction to single pregnancy
-abortion of both fetuses in mid/late gestation
-dystocia
-stillborn/weak foals
In mares, it is ideal to detect twins before fixation which occurs at:
Day 16
What is the best thing to do if 2 embryos are present in a mare?
Pop goes the embryonic vesicle - pop that shit
90% chance the remaining vesicle will go on to develop fine
What could you do in a mare if you found twins between day 16 day 35?
Trans vaginal aspiration of allantoic fluid
(Aspirate fluid from allantoic space to dry out the fetus)
What are some options for getting rid of one twin in a mare that is past day 35 of gestation?
Trans abdominal fetal puncture
(Locate one twin, go into thorax of fetus and inject Pen-G, this causes fetal death)
Cervical dislocation (dislocate one twins’ cervical spine)
Induce abortion (PGF2-alpha)
Manually dilate the cervix and extract the fetus
What are the most common signs of placentitis in the mare?
Premature mammary development
Vaginal discharge
(If discharge is present, this is beyond the ability to treat?)
What is the CTUP?
Combined thickness of uterus and placenta
List expected CTUP values for a mare
Day 271-300 = <8 mm
Day 301-330 = <10 mm
> Day 330 = <12 mm
What is the most common form of placentitis in mares?
Ascending infection from vagina
What does PGF2-alpha do?
Causes lysis of the corpus luteum
Lutalyse is:
A natural form of PGF2-alpha
Also called dinoprost
Estrumate is:
Synthetic form of PGF2-alpha
Also called cloprostenol
What brand of PGF2-alpha is often used off label in horses and why?
Estrumate (cloprostenol)
Minimal side effects
In large animals, A single shot of prostaglandin is only going to be effective in:
A mature CL
Need to wait 5 days post ovulation to induce luteolysis with a single shot
What does the CL produce?
Progesterone
(The hormone that maintains pregnancy)
Progesterone blocks ______ and inhibits _____
Heat + ovulation, LH surge
If no pregnancy occurs, the uterus secrets ____ to cause luteolysis of the CL
PGF2-alpha
Define ecbolic
Drug that causes uterine contractions
Prostaglandin can be used to treat pyometra in dogs but under what conditions?
Must be an OPEN pyo!
Cannot be closed pyo, pus needs a place to go.
If closed, pus could do into abdomen and cause peritonitis
Another function of PFG2-alpha is:
Induction of uterine contractions
What is the primary function of oxytocin?
Used to induce uterine contractions