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Does your horse have a hairless patch of skin that looks like a wart and just won’t go away? Or maybe a lump on his body that seems to be slowly getting bigger. Sarcoids are the most common skin tumor of horses. While they tend to only be locally invasive, and do not metastasize to other areas or organs, they can be quite unsightly and irritating to the horse. Depending on their location, they may also affect the normal movement of the horse, and be very difficult to remove.
Equine sarcoids are tumors of connective tissue caused by a bovine papillomavirus, a virus which causes warts in cattle. The virus is believed to be transmitted by flies. Sarcoids are frequently found on the face, legs, or at old wound sites on horses, which are all favorite landing spots for flies. It is also believed that some horses are more susceptible to developing sarcoids than others. There are several different types of sarcoids, which differ in their appearance and level of invasion into the skin and deeper tissues. These are:

1. Occult: Circular and may be hairless or thinly-haired, and may look like ringworm or an abrasion that doesn’t heal. These are more commonly found on the head and neck.
2. Verrucous: Hairless, thickened, rough, and flaky. There may be raw, ulcerated areas within the sarcoid, and this type may also look like a wart, ringworm or a non-healing abrasion. There are more commonly found on the face, body, and groin.
3. Nodular: Nodules which are firm, raised, and round. These are more commonly found on the eyelids and groin.
4. Fibroblastic: Fleshy and ulcerated, may be covered with haired skin. These may look like proud flesh or squamous cell carcinoma, and are more commonly found on the lower legs, groin, and eyelids.
5. Mixed: One region having characteristics of 2 or more types of sarcoids.
6. Malignant (aggressive): Locally invasive, multiple nodules and cords which tend to be fast-growing.

A biopsy is the best way to diagnose any of these types of sarcoids. They may appear similar to a number of other skin diseases, but when submitted for histopathology to examine the tissue, the diagnosis is usually straightforward. Treatment, however, can prove more difficult. Some sarcoids, if small and in an area where they don’t interfere with movement, may be left alone. However, these must be monitored because they may grow to the point where other treatments become very difficult to perform. Surgical removal of sarcoids is possible, but can be difficult for those on the head or legs. Sarcoids also tend to recur when surgery is the only treatment, so injection of the chemotherapeutic drugs cisplatin or carboplatin is commonly performed with surgery. Medical treatment with cisplatin or carboplatin alone, either injected or implanted as beads in the tumor may be successful. Mycobacterial cell wall extracts may also be injected into sarcoids, though in some cases they may make the tumors worse. For tumors around the eye, radiation therapy is another option. 5-Fluorouracil is a topical chemotherapy agent that may cause some sarcoids to regress. Xxterra is a topical herbal product which may work on some sarcoids, but in some cases may make the sarcoids worse.
Treatment of sarcoids can be very difficult, and no one method is guaranteed to work on all sarcoids. Additionally, they tend to become more aggressive and harder to eradicate as more treatment methods are tried. If your horse has a mass or non-healing wound on its body that just won’t go away or gets bigger, it is probably worth finding out what it is so that it may be treated more successfully. Your veterinarian can examine the area and take a biopsy for examination to determine what you are dealing with, and make recommendations for treatment based on the examination and biopsy results.

If you have any questions about sarcoids or other skin tumors, or about matters relating to your horse’s health in general, please talk to your veterinarian about them, or feel free to contact the veterinarians at New England Equine Medical and Surgical Center.

Susan E. Barnett, DVM
Jacqueline Bartol, DVM, DACVIM

www.newenglandequine.com


Introduction: Your broodmare has just delivered a colt. You are relieved that the delivery went through without complication. But you should still be observant of your mare in the 48 hours that follow parturition. A number of mares exhibit colicky signs post-parturition. These may include lying down for longer periods than normal, looking at the flank area, pawing and decreased manure production. Often these signs are associated with discomfort as the uterus involutes or contracts down. Pelvic bruising during delivery can cause subsequent discomfort for the mare when passing manure post-partum as well. Owners should also be aware of the possibility of periparturient hemorrhage, or bleeding from the reproductive tract.

What is Periparturient Hemorrhage?
Periparturient hemorrhage has been estimated to occur in only a small percentage (2-3%) of the broodmare population. There are three arteries that provide the main blood supply to the uterus. The major artery is the middle uterine artery. When a tear occurs in any one of these arteries, it more commonly occurs post-partum, although a smaller percentage of mares may bleed in the last few months of gestation. Theories speculate that the arteries undergo age related degenerative changes, losing elasticity that may predispose to tearing. There are three main sites in the reproductive tract where the bleed may occur.
1). Into the broad ligament, a thin piece of tissue that suspends the uterus and through which course the blood vessels to the uterus.
2). Into the wall of the uterus.
3). Into the peritoneum (belly). These bleeds carry a worse prognosis because they cannot be contained as well as a bleed into the broad ligament or uterine wall.

Clinical Signs: Horses that bleed from the reproductive tract may show a variety of clinical signs. Horses with serious bleeds into the peritoneum (belly) are often found dead in the field. A number of mares may exhibit colicky behavior including sweating, muscle fasciculations, pawing and acting anxious. These colic signs may be due to a hematoma stretching the broad ligament or irritation of the peritoneal (belly) cavity that is filled with blood. Other broodmares may only show subtle signs including lethargy and decreased appetite.

Diagnostics: A rectal exam may be performed at the discretion of your veterinarian. There may be concern that rectal palpation may disrupt a forming hematoma. Transabdominal ultrasound is an easy way to diagnose a bleed that has occurred into the peritoneum (belly). Your veterinarian may also perform an abdominocentesis (belly tap) to sample the fluid bathing the intestines. This sample of fluid may indicate hemorrhage. Although bloodwork may not be indicative in the early stages of hemorrhage, later on it may show indices of blood loss.

Treatment: Treatment for mares with periparturient bleeding is aimed at restoring blood volume and stopping the bleeding. Some veterinarians don’t advocate transporting the mare for concern of destabilizing the clot. If the broodmare has lost a substantial volume of blood to the point of displaying “shocky” signs, then intravenous fluids, as well as blood products may be warranted. In some cases, “permissive hypotension,” or not restoring normal blood pressure may be the aim so that a fibrin clot can form at the tear. Although bleeds into the broad ligament probably contain themselves by the pressure, certain medications can be administered to stimulate coagulation. Since blood is a good culture medium for bacteria to grow in, these mares may be placed on antibiotics so that a hematoma does not become seeded with bacteria and form an abscess. Surgery is not recommended, as it is difficult to identify and ligate (tie off) the torn artery.

Prognosis: Periparturient hemorrhage has not been associated with age or parity. There has been no link between the number of previously delivered foals and the likelihood of a mare experiencing bleeding from the reproductive tract. The prognosis for broodmare survival is good for those mares that are found alive and are treated with veterinary care. Recent studies have shown that periparturient hemorrhage has not been found to decrease fertility in subsequent breedings.

If you have questions about this problem or any other equine health issues please discuss your concerns with your veterinarian or any of the veterinarians at New England Equine.

Karyn Labbe, DVM
Jacqueline Bartol, DVM, DACVIM

As part of a physical examination, your veterinarian will listen to your horse’s heart. He or she will assess not only heart rate, but will also determine if a murmur or arrhythmia is present. A murmur is an abnormal sound heard between heart beats – the murmur is the result of abnormal bloodflow. An arrhythmia is a variation in the normal heart rhythm.

The heart: The heart consists of four chambers: right atrium, right ventricle, left atrium, and left ventricle. Valves separate the corresponding atrium and ventricle as well as the main vessel leaving each ventricle. Blood returns to the heart from the body and enters the right atrium. It proceeds through the right ventricle and then to the lungs for oxygenation. The oxygenated blood returns to the left atrium and then left ventricle before it returns to the body through the aorta. The traditional “lub-dub” sounds heard when listening to the heart correspond to closing of the valves. The “lub” is the closure of the valves between the atria and ventricles and the “dub” is the closure of the valves at the entrance of the pulmonary artery (taking blood to the lungs) and the aorta (taking blood to the body). In horses, two additional quieter sounds may also be heard. During systole, between the “lub” and “dub”, the heart muscle contracts and ejects blood into the corresponding vessel. During diastole, between “dub” and lub”, the heart dilates and fills with blood in preparation for the next contraction. The contraction, and corresponding relaxation, of the heart is well-coordinated by the electrical activity of the cardiac muscle cells.



Evaluating abnormalities: When hearing a heart murmur, your veterinarian will further classify it. He or she will listen to tell if the murmur is during systole (contraction) or diastole (dilation) or both. Based on where the murmur is heard best, it will give a clue as to which valve or structure is most likely affected. They will grade the loudness of the murmur (Grade I is the quietest, Grade VI is the loudest). If an arrhythmia is heard, they will determine its frequency and regularity.

Based on the examination by your veterinarian, he or she may recommend referral to a hospital for further evaluation. When examined by a specialist, the heart will be ausculted to confirm the findings of your veterinarian or to assess if any changes have occurred since your vet’s examination. Additional diagnostics may be pursued. An EKG or ECG (electrocardiogram) may be performed to assess the electrical activity of the heart – this can be especially useful in evaluating arrhythmias. In veterinary medicine, 3 clips are traditonally placed on the horse and the heart is monitored.


An ultrasound of the heart (echocardiogram) may also be done. This allows the veterinarian to evaluate the internal structures of the heart. Heart chamber size, muscle wall thickness and abnormalities of the valves can be assessed as well as the ability of the heart to contract and dilate normally. The ultrasound is performed just behind the elbows and most of the exam will be performed on the right side of the horse.


Common arrhythmias: Arrhythmias may be physiologic (resolves with exercise or excitement) or pathologic (cardiac dysfunction). The most common physiologic arrhythmia is a second degree heart block. The horse will “drop a beat” while in rest, however the heart rhythm returns to normal with exercise or excitement. This is a common finding in horses, especially very fit horses, and is not indicative of heart disease. No treatment is required. The most common pathologic arrhythmia is atrial fibrillation. This condition is most common in Saddlebreds and draft horses. It is described as an irregularly irregular rhythm or “shoes in a dryer”. Instead of the normal lub-dub, the beats are more chaotic and a rhythm cannot be defined. Some horses will show no clinical signs while others may show signs such as exercise intolerance (i.e. “gives up and won’t finish the race” or “can’t work as long as he used to”). Some horses convert on their own back to the normal rhythm. If that doesn’t happen, one of the available medical treatments is a drug called quinidine. The medication is given through a nasogastric tube on a set schedule – initially every 2 hours. Intravenous quinidine may be used if the oral form is not helpful. Due to the time commitment and the patient monitoring required for this treatment, hospitalization is recommended. A procedure called electrocardoversion is also available at some veterinary teaching hospitals to convert atrial fibrillation. It uses an electrical current to shock the heart back into normal sinus rhythm under general anesthesia. The prognosis for atrial fibrillation can be good depending on the overall presentation of the horse. Other arrhythmias are also possible.

Common murmurs: Murmurs can be congenital (present at birth) or acquired (develops with age). A patent ductus arteriosus is a common murmur heard in foals for the first 3-5 days after birth. This is normal and usually resolves on its own. The most common congenital murmur in horses is a ventricular septal defect. In this defect, a small hole is present between the right and left ventricle. It is most common in Arabians, Standardbreds, and Quarterhorses. The two most common acquired murmurs are mitral (valve between the left atrium and ventricle) insufficiency and aortic (valve between left ventricle and aorta) insufficiency. These murmurs usually occur in older horses and are the result of the valves not working properly and not closing as well. As a result, we hear the blood flowing backwards through the valve. These murmurs may or may not present problems for the athletic performance of the horse depending on the severity of the murmur and on the presence of other clinical signs. Other murmurs are also possible.

Please contact your veterinarian or any of the veterinarians at New England Equine Medical & Surgical Center if you have any questions.

Celeste Blumerich, DVM
Jacqueline Bartol, DVM, DACVIM


Images courtesy of: http://theunheard.wordpress.com/2008/02/17/valentines-day-fun/
http://www.capecodmendedhearts.com/EKG.jpg
http://www.uk-ireland.bcftechnology.com/ultrasound_products/applications/equine_cardiology

By Nancy Wesolek-Sterrett

Dressage Department Head, Meredith Manor International Equestrian Centre



As a young horse progresses up the training tree, we add lateral movements to his repertoire of gymnastic exercises. Leg yielding and shoulder-in are basic lateral exercises that strengthen the horse's hindquarters, develop his balance, stretch and 'straighten' his body by developing his muscles equally on both sides. To ride these exercises correctly, the rider needs to understand the corridor of aid pressures that asks the horse for a particular exercise. Then the rider needs to coordinate the application of those individual aids correctly, in the moment, for a particular horse at its current level of understanding.

Leg yielding (covered in a previous article) asks the horse to move forward and sideways at the same time while his spine stays parallel to the rail. Shoulder-in is the first lateral movement that asks the horse to bend through the ribcage as he moves on a straight line.

To perform a shoulder-in correctly, the horse must not only bend through his ribcage but also stretch his inside hind leg further under his body. As the inside hind leg stretches and reaches under the body, the horse's inside hip drops more than it does in a normal forward stride. This requires a greater muscular effort as the horse shifts his weight onto the inside hind leg and moves forward. So, as he works in both directions, the young horse gradually develops the stronger muscles he needs in order to engage his hindquarters, stay in balance and move straight along a track. For this reason, shoulder-in is also considered a collecting exercise.

Standing in front of a horse performing a shoulder-in, an observer should see the horse's feet moving on three tracks: the inside front foot on one track, the outside front foot and inside hind foot on a middle track, and the outside hind foot on a third track. If the horse is moving along a rail or wall, the observer will see the horse's shoulders moving at about a 30-degree angle to the wall. Another way to visualize this is to think of the horse taking the first step of a 10-meter (just a little less than 33 feet) circle then holding that 'shape' or degree of bend as he continues moving down the rail.

A young horse with underdeveloped muscles may try to evade the demands of shoulder-in by angling his shoulders out too far so he can leg yield on four tracks rather than engage, bend and move on three tracks. He may try to bend his neck without moving his shoulders away from the wall; a novice rider may also encourage this by asking with incorrect aids. Depending on his personality, he may slow down or quicken to avoid the new muscular effort. In the beginning, the rider's coordination of the corridor of aids for shoulder-in will be constantly correcting and adjusting the horse's position until his muscles develop enough that he is physically comfortable performing a shoulder-in.

Leg yielding on a circle is one exercise that helps the rider coordinate the aids correctly for a shoulder-in. As the horse travels on a circle, the rider gradually enlarges the circle by leg yielding or spiraling out. Once the horse does this comfortably, progressing to a shoulder-in along a straight line becomes much simpler.

It can be difficult for novice riders to 'feel' a correct shoulder-in. An eye on the ground or a mirrored arena can help the novice figure out just what a 30-degree angle looks and feels like (most novice riders attempt too great an angle when they begin riding shoulder-in). Again, think of the first step of a 10-meter circle but instead of continuing on that circle, hold the shape that the horse takes and continue riding parallel to the wall.

The rider should sit slightly heavier on the inside seat bone with the inside leg driving at the girth and the outside leg slightly back to keep the haunches from falling out. The rider should feel the horse's inside hip drop as he reaches under and across. At the first step of shoulder- in, the rider's torso and shoulders should begin to spiral as though they are riding a 10-meter circle. Then they should stay parallel to the horse's shoulders as the horse continues along the arena wall. The inside rein positions the head slightly to the inside. The outside rein redirects the horse's motion from continuing on a circle to going down the rail at a 30-degree angle from it.

Many novices make the common error of pulling on the inside rein to position the horse's head and neck, bringing the head and neck over to the inside rather than moving the horse's shoulders over. If the rider peeks down, the horse's neck and head should still be aligned with the center of the chest. If the neck is bent but the shoulders are still parallel to the wall, the rider has not coordinated the corridor of aids clearly in a way the horse understands. Remember, the shoulder-in is simply the first step of the circle. Go back to the basic circle when the shoulder-in falls apart. Try to maintain the circle shape and move the horse from your inside leg.

The rider must maintain correct hand position on either side of the horse's withers when asking for shoulder-in. A novice rider may cross her outside rein over the horse's neck in an effort to keep the horse from falling back to the rail. If the rider maintains a straight line from elbow to bit, she has a better chance at controlling the horse's shoulders and maintaining the shoulder-in. Many riders draw their inside leg up as they apply it. When this happens, they come off their inside seat bone and shift their weight onto their outside seat bone. Then, as their horse shifts his balance to compensate for the rider's shift, his shoulder falls to the outside, and then the rider usually ends up pulling on the inside rein in an attempt to maintain shoulder-in.

The rider must maintain energetic forward movement and a consistent rhythm when asking for a step in shoulder-in. If the rider does not maintain forward energy with a driving inside leg, some horses will shorten their stride to avoid dropping their inside hip and reaching under. If the rider does not use outside leg to keep the hindquarters in alignment, the horse may throw them to the outside and leg yield (four tracks) instead of performing a shoulder-in (three tracks).

When shoulder-in is not working, regroup by riding a circle. As the circle touches the wall, take one step along the rail and then go back to circling. Gradually increase to two steps along the wall, then three, etc. Go slowly in asking a young horse to increase the number of steps in shoulder-in. A novice horse or rider will increase in understanding of the aids with each attempt. ____________________________

© 2010 Meredith Manor International Equestrian Centre. Nancy Wesolek-Sterrett has earned numerous United States Dressage Federation horse awards including Bronze and Silver Medals on horses she has trained. She competes her horses at Training through FEI levels. As a Certified Riding Instructor she brings over 20 years of experience to her position as Head of the Dressage Department at Meredith Manor International Equestrian Centre (147 Saddle Lane, Waverly, WV 26184; 800-679-2603; www.meredithmanor.edu), an ACCET accredited equestrian educational institution.

By Nancy Wesolek-Sterrett
Dressage Department Head, Meredith Manor International Equestrian Centre

WAVERLY, WV--Body position influences your horse whether you are standing still or moving. Correct position is the basic skill riders must master in order to progress up the riding tree. Unless you correctly position your own body, you cannot influence your horse to use its body correctly.

If you could view yourself from the side, a plumb line held by your ear should drop straight down through your shoulder, hip and heel. Try to maintain this line as you ride. If your horse were to disappear, you would be in a standing position on the ground. As a rule of thumb, if you glance down and see your toe, your leg is too far forward. This position puts you in a chair seat, behind your horse's motion, and horses will either scoot forward or slow down when this happens. Therefore, many riders may tip forward to rebalance themselves, trying to fix the problem. This compromises your vertical alignment even more. Your torso should stay perpendicular to the ground, not tip forward or backward, as you and your horse move rhythmically in balance.

Your spine should be straight with the lower back neither rounded nor arched. Take your hand and place it in the small of your back. If your lower back bumps out, then you are slouching or rounding it. If your lower back feels hollow, then you are arching your back. You want to feel just a slight gentle curve.

You can also test the curvature of your spine by standing next to a wall with your heels against the wall. As you press your upper back against the wall, what happens to your lower back? Is there a pronounced arch? Can you press it flat against the wall? Can you press your shoulders against the wall without arching your back?

When you round your lower back and slouch in the saddle, you push the horse with your pelvis. This might make a reactive horse scoot forward or a lethargic horse slow down. When I ask a rider to sit straight, they often arch their back in order to bring their shoulders back instead of lifting the ribcage to straighten their spine. When you arch your back instead of using a firm abdominal wall to lift your torso from your hips, you push your seat toward the back of the saddle and you wiggle or 'belly dance' in the middle to absorb the motion of the horse. This can cause problems with rhythm, as it tends to cause your horse to speed up.

Your mid-section should be lifted and firm so that your pelvis and hips can absorb your horse's motion in an upward tipping motion. Think of lifting your rib cage upward or of lifting from your belly button to your chin as a strong stick holds your spine straight. With a straight spine and firm abdominal wall, your pelvis can tip up and forward to set the rhythm at sitting trot without going faster than your horse.

Your shoulders should be relaxed and down. Tension draws your shoulders up towards your ears. To feel the difference, lift your shoulders toward your ears and then drop them as though you are pushing them into your back pockets. Your shoulders should stay parallel to your horse's shoulders. For example, if your horse is doing a shoulder-in with his shoulders turned to the inside, then your shoulders should also turn to the inside instead of staying perpendicular to the wall.

Occasionally, I see a rider with one shoulder more forward than the other. If that happens, I ask the rider to take the reins in one hand and pull their shoulder into place by putting the back of the hand on that side in the small of their back (be careful not to arch your back). You can also try extending your hand straight up over your head on that side. This stretches the ribcage on that side of your body which helps reposition the shoulder.

Your upper arms should hang from relaxed shoulders with a bend in the elbows. Your elbows must flex and absorb the motion of the horse in order for you to have steady hands. The amount that your elbows will open and close depends on the gait and the degree of collection. To understand how this elbow motion feels, bounce up and down with your hands placed on a stationary object. The opening and closing motion you feel in your elbow is the same motion that keeps your hands steady at the rising trot. To understand how this motion feels at the sitting trot, bounce from foot to foot.

Many riders lock their shoulders and elbows thinking this steadies their hands but it actually creates tension that makes their hands bounce up and down. Tense hips can also cause tense elbows. To unlock tense elbows, you can exaggerate the motion learned off the horse in the exercise described above or you can say 'open, close, open, close' while riding. You can also place your hands on the horse's withers to simulate the stationary object described in the exercise above. This, however, does not always work for riders with a tall torso because it causes them to tip forward. If this is the case, then I suggest putting a strap on the front of the saddle to hold while working toward steady hands.

Your hands should also be relaxed, holding the reins as though you were holding wet sponges. Imagine you are holding the sponges tightly enough not to drop them on the ground but not so tightly that you wring out all of the water. Squeeze the imaginary sponges tightly and feel the tension in your forearms. Now relax your hands and feel the relaxation in your forearms. Your wrists should be straight with the thumb the highest point of the hand--no 'piano' hands or 'shopping cart' hands.

The placement of your hands depends on the horse's frame. You should have a straight line from your elbows to the horse's mouth. If the horse is in a stretching frame, your hands will be lower. If the horse is in a working frame, your hands will be a little higher. And if the horse is in a collected frame, your hands will be even a little higher in order to maintain that straight line. Ideally, your hands should stay within a 4-inch box right in front of the withers, never crossing over the neck or bracing downward.

As you view yourself from the front or the back, a plumb line held at your nose should pass through the middle of your chin to the middle of your pubic bone. Your midline should align with your horse's midline.

If you tip right or left of the midline or collapse your ribs on one side, think about which side of your body is stronger. Since the muscles on your stronger side are tighter, you may tend to lift the seat bone on that side off the saddle. This pushes you to the weak side. The muscles on your weaker side are easier to stretch so you may find you can stretch the leg on that side down more easily, which also tends to take you off of the opposite seat bone. If you are right-handed, for example, you probably have trouble keeping weight on your right seat bone and tend to collapse your right shoulder as you try to pull yourself back over to the right. This may even cause you to feel like your right leg is shorter than your left leg. Stretching exercises on your stronger side may help to elongate that side.


As you ride, keep the image of a gymnast on a balance beam in your mind. If the gymnast does not keep her shoulders over her hips, she falls off. Like her, your shoulders must stay directly over your hips in order for you to be balanced over your horse and able to follow his motion.

The spine of the upper body joins the hip joints of the lower body at the pelvis. This is the all-important 'seat.' Without a correct seat position, you cannot influence the horse correctly. I will come back to the critical role of the pelvis and hip position in influencing the horse when we discuss correct lower body position.