Download Floozy Mares and Sexy Geldings - Ocean State Equine Associates

Floozy Mares and Sexy Geldings
What sex hormones might mean to
your horse
What is a hormone?
A chemical messenger
that directs various cells
to perform their various
functions
Familiar Examples
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Insulin
Thyroid Hormone
Cortisol
Estrogen
Progesterone
Testosterone
Growth Hormone
EPO
A SEXY FAMILY TREE
Where do sex hormones come from?
In The Non-Pregnant Mare
• The ovaries
– Progesterone
– Estrogen
– Tiny amount testosterone
In The Stallion
• The Testis
– Testosterone
– Estrogen
• The adrenal gland
• The adrenal gland
– small amounts of
progesterone and
testosterone
– small amounts of
progesterone and
testosterone
MARES CAN BE AMAZING
Does your mare ever
look like this?
Or this?
OR THIS!!
Does she terrorize her
buddies?
“She’s ALWAYS in heat!!!”
What you may be observing
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Cranky
Affectionate?
Easily Distracted
Squatting
Urinating Frequently
Lifting her tail
Seem “uncomfortable”?
Hallmark of True Estrus Behavior
CYCLICAL!
Clues
• Keep a calendar next to her stall
– Mare to mare variation in behavior
• Hormonal therapy works on her!
– Altrenogest (e.g. regumate)
• shuts down estrus completely
But XYZ worked so well!
XYZ
• Depo-Provera
• Progesterone implants
• Supplements
– B vitamins
– Raspberry Leaf
– Valerian Root
–?
So it is hormonal….
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Embrace it! - geldings are boring!
Altrenogest - works
Marebles - may extend times between
Breed her! - old timey solution may backfire!
Spay her – permanent –you better be sure
Vaccine???? - innovative option in Australia
Marebles
So, OK she isn’t in heat all the time
• Dominance/submissive behavior
– More studies needed to understand this
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Uterine infection
Bladder stones or cystitis
Lameness/back pain
Ulcers
My sweet mare is
striking, biting and
mounting!!!
Granulosa Cell Tumors
-benign tumors of the ovary
-usually one side
-other side does not cycle
-excessive testosterone
What you may be seeing
She used to act like this
Now she acts like this
Diagnosis
Diagnosis
• Symptoms
– Stallion like behavior
– Not cycling normally
• Ultrasound
– Honey-comb appearance?
– One larger ovary
– One tiny ovary
• Lab work
Treatment
Great News!
• Will take one season
following surgery the
other ovary should
begin cycling normally
• Then you can go back to
dealing with her normal
personality!
The Boys
Is yours delightful?
Or……………………….
Cryptorchids
Testosterone can do crazy stuff
What are you observing?
Does your gentleman do this?
Or this?
What are you observing?
Is he generally like this?
This look more familiar?
He may just have a “girl friend”
Or…..
Developmental Process
• Usually descends before
or within 2 weeks of
birth
• Anecdotal evidence that
it can descend without
treatment by 2-3 yrs of
age
Hallmarks
• Behavioral
• One or no obvious testical
– Under skin but very high and small
– Inside inguinal canal
– abdominal
Cryptorchid factoids
• Abdominal testis does not produce sperm but
does produce testosterone at high levels
• Behavior often more pronounced than normal
stallions
• Rarely but possibly bilateral
• In some lines of stallions appears to be
hereditary
• Considered un-ethical to breed uni-lateral
cryptorchids (these guys are fertile)
Cryptorchid factoids
• The retained testicle is
always smaller
• Can be the left or right
Diagnosis
• External palpation by
veterinarian
• Ultrasound external and
internal
• Blood tests for
testosterone and
possibly estrogen
Cryptorchid Treatments
Your old guy a
bit rowdy????
-Sexy Gelding Syndrome
-Excess production of
hormones from the pituitary
-Increase testosterone made
by the adrenal glands
-usually seen with other
obvious signs of Cushing’s
Disease
Random Hormone Topics
Random Hormone Topics
• Progesterone given to stallions to reduce sexual
behavior
– May decrease testosterone?
• Progesterones given to all sexes to “quiet” them
– Anecdotal-no scientific evidence
• Estrone (form of estrogen) sometimes given to
horses with “sticky” stifles
– thought to relax the ligaments?
QUESTIONS??