Oct 7, 2014 | Ailments, Breeding
Cloning!
In 2008 the National Cutting Horse Association voted to allow cloned animals to compete in their aged events. There were at least 2 clones entered in the 2009 NCHA Futurity show for 3 year olds, but neither ended up competing in the event. Cutting horse trainer Phil Rapp trained both fillies – Playboys Ruby Too, a clone of Playboys Ruby, and what’s on Tap, a clone of Tap o Lena. Neither filly was ever on the top of his list for the Futurity, and he called their abilities “average”, even going on to say that What’s on Tap “did not progress as a cutting horse”, and that Playboys Ruby Too was the stronger filly, but “needed to do more than turn both ways”. The mediocre performances of these two clones confirms that genetics alone don’t make a superior athlete, and that cloning a world champion or Olympic medalist doesn’t ensure success in the top levels of competition.
In 2012 the FEI (International Equestrian Federation) made a statement that clones and/or their offspring would be allowed to compete in international events, including the Olympics. The decision came too late for it to effect the 2012 summer Games. Horses in Olympic disciplines like eventing, dressage, and show jumping are often considered ‘aged’ – older than 10 – before they are experienced enough for the international stage, so even if clones were being aimed at the Olympics, they probably wouldn’t have been ready yet. Maybe in 2016?
Polo may be the one exception where we should expect to see cloned horses competing on a regular basis. Polo ponies are being cloned at a faster rate than any other type of horse. By 2013, one owner alone, top polo player Adolfo Cambiaso, is reported to have cloned his top horses almost 100 times! Adolofo says that his goal is to one day complete an entire polo match riding only cloned animals. In 2013 he took a step toward this goal by riding one of his clones, a mare named Show Me, during the Championship match of the Argentine National Open, which his team won. He scored two goals while riding the mare, who is a clone of an American Thoroughbred, named Sage. Cambiaso currently has over 50 clones in training, and more will be coming of age for competition soon.
Registered Clones? Cloned racehorses?
You won’t be hearing about clones of Secretariat, Man O War, or First Down Dash any time soon. Why? Both The Jockey Club, which registers Thoroughbreds, and the American Quarter Horse Association (AQHA) have policies that ban the registration of clones or their offspring. Thoroughbreds have to be registered with the Jockey Club in order to race, and similarly, QH racehorses must be registered with the AQHA. For this reason, it doesn’t make sense to go to the effort to clone racehorses, at least not until the rules on registration change, and those changes may be coming soon.
The AQHA is in the midst of a long standing legal battle over clone registration. A group of cloned QH owners filed a lawsuit against the AQHA in April of 2012, arguing that clones (and therefore their offspring) should be allowed to be registered. The AQHA refused to give in, stating that over 85% of their members were against the registration of clones. In July of 2013 the court ruled against the AQHA, but the organization is appealing the decision, and opening arguments of the appeal begin this very week.
Oct 2, 2014 | Breeding, Uncategorized
Equine Coat Color Genetics, Part 1: Black, Chestnut, Bay
If I breed a gray mare to a bay stallion, what color will the foal be? If I bred two palominos, how did I end up with a chestnut foal? Equine coat colors actually follow some fairly straightforward rules – in fact, the same ones discovered by Mendel and his infamous peas that you may have learned about in biology. The first thing to understand is that each horse has two complete pairs of chromosomes – one that came from its sire, and the other from its dam. This means it has two copies of every gene, one from mom, and one from dad. The way the two copies of each gene interact with each other, as well as the interaction between separate genes, is the basis for all things genetic, including color.
We use letters to identify which types of each gene (which allele) the horse has inherited. Capital letters identify the dominant allele, and lower case letters stand for a recessive allele. Most of the time, recessive traits or characteristics are only observed if the horse inherits the recessive allele from both parents.
If for example there was a single gene for speed, (there’s not, but for example), then the letters we might use would be ‘F’ for fast, and ‘f’ for slow. If a horse was ‘FF’ (got ‘fast’ from both parents), it would be fast, and if it was ‘ff’, (got ‘slow’ from both parents) if would be slow. But if it was ‘Ff’ (got ‘fast’ from one parent and ‘slow’ from another, then it would still be fast, because ‘fast’, big ‘F’, is dominant to ‘slow’, little ‘f’. The dominant allele trumps the recessive one.
Another way to look at this:
FF = fast horse
Ff = fast horse
ff = slow horse
The ‘extension’ gene: Black, or Red.
The first gene you have to understand when talking about horse colors is the ‘Extension’ gene. Never mind its name, think of this gene as the “black or red” gene. The letters are ‘E’ for black, and ‘e’ for red (chestnut). Black, big ‘E’, is dominant to red, little ‘e’. All horses have this gene, (all horses have every gene), even ones that are colors other than black or chestnut. The other colors exist because of the way other genes interact with the extension gene.
EE = black-based
Ee = black-based
ee = red (chestnut)-based
You might be wondering, if black-based is dominant to red-based, why are there so few black horses compared to bays or chestnuts? Keep reading.
‘Aguti’ makes Bay.
The ‘Aguti’ gene controls black distribution across a horse’s body. Since red-based horses have no black, they will have two copies of this gene, but they won’t play in role in determining the horse’s color. On a black-based horse, the aguti gene determines whether the black will be all over the horse or only on certain parts (like the mane, tail, and legs). There are three alleles for this gene: ‘A’ restricts black distribution the most, (black main, tail and legs only), ‘At’ restricts black a little, and ‘a’ does not restrict black at all.
AA = black restricted to main, tail, legs
Aa = black restricted to main, tail, legs
AtAt = somewhat restricted black
Ata = somewhat restricted black
aa = black is unrestricted, black all over the body
So, combine this with what you know about the extension gene and you get:
EE or Ee (black based) with AA or Aa (restricted black) = Bay horse.
EE or Ee (black based) with AtAt or Ata (some black restriction) = Seal brown horse.
EE or Ee (black based) with aa (unrestricted black) = Black horse.
The reason for few truly black horses is that there are many black-based horses, but most of those turn out bay. Why? Because the big ‘A’, which restricts black, making bay, is dominant to the little ‘a’, and there happen to be a lot more big ‘A’s floating around in the horse population than little ‘a’s.
Remember, the aguti gene does not matter on red-based horses.
It only controls black. So:
ee (red-based) with AA, Aa, or aa (or any combination of aguti alleles) = Chestnut horse.
Sep 26, 2014 | Breeding, Uncategorized
Cloning!
Clones – Where are they now?
I overheard Dr. Bourke talking about cloned horses the other day. Seems like there are a quite a few of them out there now! I’m still not sure that cloning is a good idea, but it was interesting to learn what the cloned horses are up to.
The world’s first cloned horse was born in Italy way back in 2003 – a Haflinger mare that was named Prometea. What’s really interesting is that in this case, the mare that carried the pregnancy was also the mare they took the genetic material from – she gave birth to her own clone!
In 2005, Italy did it again, producing a clone of the famous endurance Arabian stallion Pierez. Then things really took off in 2006 when Texas A&M University announced the birth of FIVE clones of the cutting horse stallion Smart Little Lena. That same year the world’s first commercially cloned horses were born in Oklahoma – copies of top Quarter Horse cutting mares Royal Blue Boon, Tap O Lena, and Playboys Ruby. Since then, there have been handfuls of cloned horses born from several different equestrian disciplines. Examples include show jumping greats ET, Gem Twist, Calvaro V, and Sapphire, dressage stars Jazz and Rusty, international event horses Che Mr. Wiseguy and Tamarillo, barrel racer superstar Scamper, and several other well known cutters including Doc’s Serendipity and Jae Bar Fletch.
Clones Are Reproducing: Prometea is now 11 years old, and in 2008 she had her first foal, a colt, which was reportedly healthy. This was the first offspring of a cloned horse, but there have been several others since. The cloned stallions of Pierez, ET and Gem Twist all have foals on the ground. Pierez is even a grandsire. His first daughter gave birth to a colt in 2012.
Clones for Sale: The Smart Little Lena clones are now 8 years old. One of the five died at the age of 4 from bladder cancer. The remaining four stallions were sold by the syndicate that owned them at the 2009 NCHA World Finals sale. They went for $2400, $3000, $27,000 and $28,000. The highest selling stallion was exported to Australia and now stands at stud for a fee of $1500. One cloned polo pony mount from Argentina sold for a whopping $800,000 in 2010.
Clones in Competition: Because of the high costs involved with producing a clone (roughly $150,000 per horse) it is unlikely that very many will enter competition. The horses being cloned are all from the top ranks of their disciplines, so it would be difficult for the clones to perform as well as the original, let alone surpass or improve on their achievements. Clones have the genetics of superstars, so from a business and breeding standpoint, they have nothing to gain from competition, and everything to lose. For this reason, most clones will be used for breeding purposes.
However, several performance horse organizations have opened the door to allow for cloned animals in competition.
Aug 21, 2014 | Ailments, Leg issues
It’s simple but it’s not easy. This saying can be used to describe so much about our horses. Surely it’s simple to keep your heels down, shoulders back, and eyes up and yet I definitely don’t find it easy! Proper trimming of a horse’s foot is similar. There are a few basic principles to proper trimming and yes they are simple but they often aren’t easy.
Our horses are a marvel of engineering and the foot is the epitome of that marvel. Just think about your horse cantering across a field. On the left lead the right front foot is carrying all of the weight along with the forces created by cantering during the stance phase of the gait. What does all this mean for your horse and his foot? Back to high school Physics we go….
During movement the coffin bone rotates around the very center of the short coffin bone creating a center of rotation. Our goal when trimming feet is to put this center at the ideal spot for forces on the navicular bone, deep digital flex-or, and the structure of the heel. This generally translates to half the hoof mass being behind this line and half in front. For the geekiest among us, that gets us the shortest moment arm possible. In the picture here that means this horse should have his toe and heels brought back since too much of the foot is in front of the vertical line right now. The lateral (image from the side) view only gives us part of the information we need to give our horses the perfect foot. The bottom of the foot tells us even more.
There are three important lines on the bottom of the foot. The first one is across the heels. The second is drawn down the center of the foot from front to back and the third is across the foot at its widest point from inside to outside. These lines give you a guide to the structure of the hoof capsule, the bones underneath, and the best way to trim the hoof.
Let’s begin with the line at the heel. The heel should be at the widest point of the frog and the inside and outside heel should be at the same place. The heel must be rasped down to this level! We have all heard don’t touch the heel so they can grow more but it just doesn’t work that way. The heel must be brought back to the widest part of the frog or it is mechanically compromised and this WILL cause big problems later.
Next, the line down the center of the hoof. This line should not only cut the foot in half but also cut the frog in half. If it doesn’t the frog is telling you there are problems! This line does have some wiggle room based on your horse’s conformation but it is only a little wiggle room. For instance, a pigeon toed horse will carry more foot to the inside and that will be normal for them.
Finally, the line across the widest part of the hoof. Again half the foot should be in front of this line and half behind. The half behind is determined by the spot where the heels hit the ground. This is why it is so important to have the heels at the widest part of the frog. If the foot starts with the heels at the right place, this line will give you an excellent guide to proper break-over location.
These lines are the start of everything we do with feet. A horse with good feet keeps these proportions without the need for shoes. However, bad feet, lameness, or laminitis cause the need for shoes to recreate these proportions. And that’s exactly what a good farrier does with shoes: recreates these proportions. It’s not easy but it really is simple!
Jul 28, 2014 | Ailments, Feed, Pests
Tough Love in the Summer Time
Look at this sad, abused, little pony! Muzzled, blindfolded, and NO food in his hay net! Is this your horse at feed time? If he is, then know that we understand all those conflicting emotions you are feeling right now. This is Dr. Bourke’s pony, Flash. Left to his own desires in the summer, Flash quickly becomes a rolly polly little thing, with a Body Condition Score of 9 out of 9. (Think Pillsbury-Dough-Boy fat). His handsome white nose gets chapped and sunburned, and fly irritation causes his eyes to weep.
It’s feed time and your horse is looking at you with that pathetic face. How can you not offer him something in his bucket?!? Back before Dr. Bourke knew better, Flash was allowed to graze free choice, and he even got grain! Dr. Bourke didn’t understand the connection between easy keepers and the risk of laminitis. Flash was very lucky that he made it through several Virginia summers without any signs of foot soreness. Sometimes he would get a fly mask on him, but it would fall off in a few days – or a few hours – and then she would give up.
It just takes so much effort. It also can be expensive – all of those muzzles and fly masks add up! But is it worth it? Absolutely. Because our veterinarians see the consequences of not putting on fly masks and grazing muzzles. Together the muzzles and fly masks help prevent laminitis, sunburn, skin cancer, and habronema ‘summer sores’ from fly exposure.
Now Flash is forced to wear a grazing muzzle from May through August, when the grass is thick and green. He also sports a nice fly mask religiously, gets only coastal hay, and we’ve switched him over to a ration balancer instead of grain. I ride him regularly, even when it’s hot. She also has to live through his sad faces at feed time when the Thoroughbred gets 5 lbs of tasty Ultium and Flash gets a measuring cup of the ration balancer – really just a vitamin and mineral supplement.
All of this takes discipline. It means purchasing several fly masks at the beginning of the season in order to have one ready and on hand when the first one gets torn to shreds. It means tromping through the field several times a week in search of the missing fly mask. It means occasionally jerry-rigging the muzzle in order to get it to fit properly, or adding padding to make sure it doesn’t rub his face. It means committing to riding even when the temperatures are high and the humidity is higher. But it also means no skin cancer or laminitis.
What can you do for the horse who refuses to wear a fly mask? Zinc oxide on any white skin, children’s roll on sunscreen, and days spent in a stall are great options many of our clients use. Stall time also helps the overweight horse. Grasses are highest in sugar content one half-hour before and after sunrise and sunset. By keeping your horse in during these times you will dramatically reduce their sugar intake.
Summer is a battle! And horses can’t handle like I do: sleeping in the AC in the Clinic all day. Be prepared and talk to our Doctors and technicians about the best strategy for you and your horse. Always remember: May your litter box be clean and your food bowl full!
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