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Line breeding in horses. Do's & don'ts?

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Apr 8, 2005
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I have 2 registered AQHA mares that foaled in 2003, one had a filly and one a stud colt. One of the mares is a grand-daughter to EasyJet and the other is a great-granddaughter. Both of the foals were sired by the same AQHA Foundation stud, thereby making them half-brother and half-sister.
Question: 1) Would it be OK to breed the half-brother to his half-sister?
2) Would it be OK to breed the stud colt to the EasyJet grand- daughter mare, since he is out of an EasyJet GREAT-grand- daughter? Both of the mares have un-related mothers.
I would greatly appreciate any input or recomendations regarding this subject.
1) don't do, you may be concentrating like genes of a bad trait or you could concentrate the genes of a good trait, don't take the chance.
2) some different gene pool added, less chance of concentrating genes, go for it, I have a double bred Hancock right now that is pretty awesome.
I have Tested my line every now and then

Crosses that seam to work
Father X Daughter
Brother X Sister
1/2 Brother X 1/2 Sister

Mother X Son = Look out - Bad X

Just my experance - - I've found 1 or 2 Bred troubles this way and put whole Litters down

I'm sure that everyone knows that when you line-breed or inbreed, you magnify the good traits. You also magnify the bad ones. So if you are contemplating doing this, you need to reasearch genetics to find what bad traits are there. It shouldn't be just a happenstance mating, with your fingers crossed. A live animal is produced as a result.

It would scare me. Why take a chance when there are so many good horses out there to breed to?
I agree with FH... I've had a few catch colts that were inbred- one I remember was dumber than a post and never did turn out....I had a 5 year old gelding I sold last year that was a catch colt (his sire was his 1/2 brother)- he turned out to be a really good horse-very athletic and cowy...

First thing you need to decide in making a breeding decision is what do you want from your foal--ranch horse, specialty arena horse, cutter, show, etc.--what are you hoping for in size--breed up size, breed down....What trait does each mare have that you want to improve, or do away with- better withers, better feet, more muscle, more speed, cowsense, etc.?... With all the proven stallions out there you can get some pretty good guarantees of what they will throw into the mix...
The First thing one must decide is
Are You Going to be a Breeder or a Collector?

As a Breeder I have to know what I am breeding is producing - - because some Breeders tend to ignore or just plane lie I had to develop the Guts to do what it take to look honestly at what I am producing. (Horses, Cattle, Sheep, Dogs, and more)

One of my Line Breedings produced a Monorcid (sp) (one testical) offspring - - It took 2 years of Detective work weeding through the Lies and Untruths to track this down.

It HURT but I had to take drastic steps to stop that Line on our place and in MY History as a Breeder.

50 years ± ago a Highly Respected Augus Breeder told me:
A Breeder/Detective that wants to keep Friends must learn to keep their mouth shut.

My wisdom:
An open mouth gathers more Lies :!:

Just Produce - Let Time and Others Brag For Ya :oops:

I'll ad one more:
A Stable Blind Breeder can't be a Good Breeder 8)
FWIW: years ago i worked for a horse breeder that had 2 really high priced stallions; one was an old-time bred (ie, not really fashionable with the show crowd) guy, classic build for the breed and threw that and his sweet personality to his colts. the only thing this guy asked was a mare in the stall next to him: if the mare was taken out for teasing/breeding, he'd yell about it, but calm down as soon as (any) mare came back next door. these were solid walls, 14' high between stalls. apple-boy KNEW if there was a mare next door....

the other stallion they stood was much more fashionable--he sired babies with a lot more "fire" and "action", but unfortunately, there was the occasional club-footed foal. these were NEVER mentioned, free services were offered if everyone involved kept their mouth shut, etc, etc.

the real kicker in my book was, this stallion was a man-killer. he had to be chained up from outside his stall (after being suckered with grain to get him close enough to hook a chain to his halter), in order to even clean his stall--he'd run a groom underneath his hay-feeder twice before they figured that out (and this was a corner feeder, a good thing the groom was 1) tiny and 2) had no other options for employment). this stallion would try to go thru the stall to get at you if you were sweeping the aisle in front of his stall--i used to try to de-condition him by sweeping the aisle in front of him over and over, but it just made him crazier.

i was young, what the hey. my point is, i don't care how pretty they are, if they don't do what they're supposed to do, what's the point? who cares what they look like, if they don't perform, get rid of 'em.

the bottom line was, and is, if a bad breeding gets the money, people will do it, in any type of breeding--look at history... bette quit again. but it's one og my pet peeves..lol :roll:
One of my pet peeves breeding horses is the fact that if someone gets a mare to ride and she isn't very good; either bad temperment, unsound, rough riding, WHAT EVER~they will just breed her. Has anyone besides me ever noticed this?

Personally, I think the mare has more to do with how the colt turns out, than the stallion does. After all, that colt lives with the mare til it is weaned. Not enough people ride their mares before they breed them and don't really know what good or bad traits the mare has.
It NOT WHAT she KNOWS - I don't have to ride a mare to deside if she has brains or personally and I can watch her move and tell if she's rough or smooth.

Now Studs
So much has to do with the way they were raised and Handled. I can watch a Handler in public and see how he handles himself around women, childern, others and just about tell you how his Stud will act.

I like to settle the mares and turn my yearling Studs out with them - Young Studs sure learn their Manners from old settled mares as they come in to age and the mares seem to know their babies. I've never had a colt hurt badly.

Give me a Stud for two weeks and I'll give back a "Gentleman" (or a dead horse) how long he stays that way is up to you. (I have yet to hurt a horse badly)

The worst stud I've seen was "Silky Sullivan" - he put the two Handlers before me in Traction while still in his stall. The first time I handled him was fun - I had his lead in my left hand and my right hand in his halter to keep him OFF me. 30' from the breeding shute he went up on his hind legs taking me for a ride.

In 10 days he could be ready to mount and I'd raddle his chain and he'd back off.

You want to get their respect and teach them NOT brake their sprit.

"Holly Ember" was to smart for his oun good - I had him one week when I took him to a Parady of Stallions - a lady came up and was petting him - asked his name and jumped back saying his a killer!

Not any more! I said
Thank you all for the input to my original post. If I did breed the combintions stated in my original post, could the foals be registered with the AQHA? Also, one of the reasons I am considering line breeding is my limited availability of registered stud horses in my area.
Ranchero said:
Thank you all for the input to my original post. If I did breed the combintions stated in my original post, could the foals be registered with the AQHA? Also, one of the reasons I am considering line breeding is my limited availability of registered stud horses in my area.

Ranchero- I'm not aware of any AQHA rule that would prevent you from crossing either cross- they pretty much leave breeding decisions to the breeders-- only rule I know of is that each parent animal have an AQHA reg number and both would need DNA typing on file before the foal could be registered.....They do forbid registrations of defects like parrot mouth etc. Before I did the mating tho I would call their office and double check first...
Ranchero, as you may have gathered, line breeding is a tool saved for breed evaluation on a long term basis. I had a line bred son of 2 eyed Jack - 2EJ was as complete a horse as ever raised, but he couldn't stand up to line breeding. I can't remember where in the pedigree, but as I remember, Walter Merrick used line breeding in the jet deck line so you may be a little safer.

The AQHA allows seman be shipped and registered, so don't sweat your location.

With Easy Jet mares, I'd call Dwight Krebs in western Ks and talk him out of a couple Flying X 6 breedings - do a search on Krebs or x6. Krebs has a web site.

my two cents

Don't do it. It is in breeding pure and simple. How come HYPP became a problem???? two recessive genes. Say what you want, it will bite you in the butt sooner or later,

I think the breed organizations should ban registering of these horses,

like I said, my two cents,

I Tend To Agree with you (for the average Breeder or Hobbie Breeder)

HYPP may not have developed if the orginal breeder(s) would have had the intestinal fordatude(sp) or put voice to do what was/is called for.

To this date most horse owners do not understand it - miss treat it - and pass it on - with out giving voice to it.

Equitable Breeders will "do what it takes to stop it!" something that should have been done years ago.

I'd rather Die with Respect than $$$$$
In the Feed Store 3 weeks ago "A Breeder" was trlling every one his horse could not eat "corn" because his horse had HYPP :???:

Please Test your horse and don't breed anything that Teat +
Sharon J. Spier, D.V.M., Ph.D. University of California at Davis School of Veterinary Medicine, Department of Medicine

If your horse has been tested and is positive for the mutation causing HYPP, and has not shown any abnormal clinical signs, do not change anything in your current management. If your horse does show any problems, you will probably want to know how to best manage an episode of muscle tremors or paralysis and how to prevent these episodes from occurring again.

The following lists are emergency treatments for HYPP.

Treatments that are effective include the following for an acute attack:

For a mild episode (muscle tremors, horse not down)

Exercise horse (walking or longeing) - Use caution as the horse could stumble and fall. Exercise stimulates adrenalin which helps replace potassium inside cells.
Feed grain (oats, or ""corn""-oats-barley (dry), or you can use light Karo syrup for a glucose supplement). Feeding carbohydrates supplies glucose which stimulates the release of insulin which promotes potassium uptake by cells.
Give acetazolamide orally (3 mg/kg). This is usually 6 to 8 tablets if the tablets are 250 mg each. Acetazolamide increases potassium excretion from the kidney and also affects glucose metabolism.
For a severe attack, immediate veterinary attention is necessary. If the horse is down and unable to stand, have your veterinarian:
Place IV catheter and administer 23% Calcium gluconate (150 cc in 1-2 liters of 5% glucose / 500 kg horse). The majority of horses respond immediately to this and stand up.
If no response, follow with 1 L 5% sodium bicarbonate intravenously. (Dose is 1 meq/kg).
Still no response, give 3 L 5% dextrose IV, and monitor potassium levels in blood.
All these treatments help to stabilize the muscle membranes and lower blood potassium.
It is best to have the veterinarian draw blood prior to initiation of treatment and analyze the blood potassium and muscle enzyme concentrations. This can be helpful to confirm that the horse was suffering an attack of HYPP and not something else (like colic, for instance).

For control of episodes:

Regular feeding and exercise schedule. Avoid fasting or water deprivation. These horses do better if allowed access to a paddock or pasture rather than strict stall confinement. Daily or nightly turnout is helpful.
Mix alfalfa with grass hay or oat hay and grain (oats best) to decrease potassium content of diet. Many owners report that their horses do very well on grass hay alone or pasture. Feed equal amounts of hay and grain two to three times daily. Avoid rapid changes in diet.
Acetazolamide (Diamox) - a diuretic - (2 mg/kg orally twice a day). Many halter-horse owners continue to feed alfalfa hay as the only roughage but maintain their horses on this drug for all or most of their life. This drug is a forbidden substance as ruled by the AQHA and AHSA

It has come to my attention that acetazolamide is not always available from human pharmacies. Another drug which has been used is hydrochlorthiazide at a dosage of 0.5 mg/kg twice a day by mouth.
Inform your veterinarian of condition prior to any general anesthesia as this may precipitate an episode of paralysis. If your horse is receiving medication, maintain them on therapy before and after surgery or anesthesia.
Use common sense while hauling, be sure to stop and water the horses frequently (every 2 hours).
Many horses with this trait are asymptomatic and have very successful careers. Most horses can be managed easily with good care and can still bring great pleasure to their owners. Please put this condition into perspective with regard to many of the other conditions that our horses can have.

Please Note: Effective 7/1/99 the fee for HYPP testing will be $50 @ horse
I don't underrstand this part

Feed grain (oats, or ""corn""-oats-barley (dry), or you can use light Karo syrup for a glucose supplement).

¿¿¿DRY and Karo???

A friend called me for his friends mare that was sick with HYPP

I took molasses mixed with water and soaked peet pulp in to soak everything up and mixed it in with grain so it was very wet and feeded it to the horse.

Then had them walk the horse out - - It got better pretty fast

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