Risk of encephalitis gains as summer wanes

If you have not already done so, please have your horse vaccinated for viral encephalitis and Rabies.

Risk of encephalitis gains as summer wanes: By Alice C. Elwell That's what experts are saying in the wake of more mosquitoes testing positive for Eastern equine encephalitis, a virus that has curtailed nighttime regional activities for several summers now. This year, it's worse, experts warned. ...
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Colic in Broodmares: Special Considerations

Colic in Broodmares: Special Considerations: It's no secret that when complications arise around foaling time, they can be life-threatening for either mare or foal. A relatively common complication for broodmares is peripartum (the last month of gestation or the first few months after delivery) colic.

Many questions remain on cribbing - researcher

Cribbing is also a risk factor for middle aged horses to develop a certain type of small intestinal intrapment/twist called an epiploic foramen entrapment.

Many questions remain on cribbing - researcher: The underlying mechanism behind cribbing is still not completely explained, says a US researcher who has reviewed many studies conducted into the behaviour.

AAEP Resources Help Practitioners, Horse Owners Prepare for Hurricane

Foals are a speical type of colic. Other than meconium impactions shortly after birth, they rarely get simple intestinal problems. Colic in a foal is serious and should be investiaged immediately. I thought this was a nice summary of the process, similar to the adult horse we posted earlier. However the author's comment about ultrasound being used to seldom examine adult horses is not accurate. At least at BVEH, the vast majority of colic's will have an abdominal ultrasound screening as part of the workup. - Ben Buchanan

.AAEP Resources Help Practitioners, Horse Owners Prepare for Hurricane: AAEP urges horse owners to revisit disaster protocol as Hurricane Irene approaches East CoastAs Hurricane Irene moves toward the...

Congenital Flexural Limb Deformities in Foals

Congenital Flexural Limb Deformities in Foals: After 11 months of gestation and caring for the mare and watching her belly expand, delivering a healthy foal is one of the best experiences for a horse owner. Sometimes, however, foals are born with flexural limb deformities....

10 Tips for Choosing the Best Hay for Your Horse

               High-quality hay can be an important source of essential nutrients in your horse’s diet. A horse’s protein and energy requirements depend on age, stage of development, metabolism and workload. A mature horse will eat 2 to 2.5% of its body weight a day, and for optimum health, nutritionists recommend that at least half of this should be roughage such as hay.  For a 1000-pound horse, that means at least 10 pounds of roughage each day. 

Hay generally falls into one of two categories – grasses or legumes.  Legume hay is higher in protein, energy, calcium and vitamin A than grass hays. While hay alone may not meet the total dietary requirements of young, growing horses or those used for high levels of performance, high-quality hay may supply ample nutrition for less active adult horses.

            Once you’ve determined the best category of hay for your horse, most people select hay based on how it looks, smells and feels.  Use the following tips from the American Association of Equine Practitioners to select the best hay for your horse:

1.      It’s what’s inside that counts.  Ask that one or several bales are opened so you can evaluate the hay inside the bales.  Do not worry about slight discoloration on the outside, especially in stacked hay.

2.      Choose hay that is as fine-stemmed, green and leafy as possible, and is soft to the touch.

3.      Avoid hay that is overcured, excessively sun-bleached, or smells moldy, musty, dusty or fermented. 

4.      Select hay that has been harvested when the plants are in early bloom for legume hay or before seed heads have formed in grasses.  Examine the leaves, stems and flowers or seed pods to

determine the level of maturity.

5.      Avoid hay that contains significant amounts of weeds, dirt, trash or debris.

6.      Examine hay for signs of insect infestation or disease.  Be especially careful to check for blister beetles in alfalfa.  Ask the grower about any potential problems in the region.

7.      Reject bales that seem excessively heavy for their size of feel warm to the touch, as they could contain excess moisture that could cause mold, or worse, spontaneous combustion.

8.      When possible, purchase and feed hay within a year of harvest to preserve its nutritional value.

9.      Store hay in a dry, sheltered area out of the rain, snow and sun, or cover in the stack to protect it from the elements.

10.  When buying in quantity, have the hay analyzed by a certified forage laboratory to determine its actual nutrient content.

Remember that horses at different ages and stages of growth, development and activity have different dietary requirements.  Consult your veterinarian or a qualified equine nutritionist when formulating your horse’s ration.  He or she can help you put together a balanced diet that is safe, nutritious and cost-effective. More information about nutrition also can be found online at the AAEP’s horse health Web site,  www.myHorseMatters.com.

Reprinted with permission from the American Association of Equine Practitioners.

BVEH Veterinarians speak at TEVA

Multiple veterinarians from BVEH were invited to speak at the recent annual meeting of the Texas Equine Veterinary Association (TEVA). Dr. Terrell Buchanan spoke about match racing. Dr. Ben Buchanan spoke about endocrine disease in horses, piroplasmosis, and farm biosecurity. Dr. Charlie Buchanan spoke as a member of a panel on treating Cutting Horses. It is always an honor to be invited to speak, and a testimony to the effort BVEH gives to provide the highest level of cutting edge care to horses.

Herbal Therapy

Dr. Shana Buchanan is available for appointment and consults at the Navasota office the first and third Monday of every month.

Herbal Therapy:

Throughout history, people have used herbs for healing. Herbal medications are derived from plant, animal and mineral sources. Some philosophers believe that our ancestors studied an assortment of plant environments to determine the specific properties of herbs. Others believe that animals guided humans in the use of plants, and still others believe that herbal medication evolved from trial and error. Did you know that digitalis, a common heart medication, is derived from the herb foxglove? This shows that modern medicine also relies upon properties of certain herbs. Today herbs are used in conjunction with Western drugs for the treatment of cancers, viruses, and chronic debilitating diseases. With the exception of surgical conditions, herbs can be used to treat almost any condition. In Traditional Chinese Veterinary Medicine (TCVM) the ailment and the individual are taken into account for diagnosing and treating a disease. Luckily, herbs are generally well tolerated in animals.

There are several ways to classify herbal medications. Herbs can be tonics. Tonics are medications that gently nurture and strengthen and individual without the unwanted side effects. As a result of the strengthening that occurs, the body can prevent future problems and diseases. Therefore, the herbs can be used as preventatives. Some herbs have antibacterial properties. Others have anticancer characteristics. Today we typically do not treat an animal with just herbal medication, but we incorporate the Western protocol with herbal medicines to strengthen the treatment and to limit the unwanted side effects of Western drugs.

Each herb that is ingested has a specific flavor, and each flavor has a specific function that is associated with a meridian. Sweet herbs strengthen and are usually associated with the Spleen and Stomach Meridian. Sour herbs dry, restore and sooth inflamed mucous membranes of the respiratory system, gastrointestinal tract and the urinary tract. These herbs are called astringents and are associated with the Liver Meridian. Hot, spicy, pungent and/or acrid herbs disperse circulation and energy and are associated with the Lung Meridian. Bitter herbs help clear infection and detoxify the system and are related to the Heart and Liver Meridians. Salty herbs soften masses and nodules and are associated with the Kidney Meridian.

Herbs can also be classified according to temperature and direction. Herbs can be hot, cold, warm, cool or neutral. Herbs can direct circulation towards the areas of the body that need them. This can be an upward direction to help the Yang of the body, a downward direction to help the Yin of the body, and an outward direction which increases the circulation near the body’s surface.

Herbal actions are derived from the Eight Principles: Yin/Yang, Cold/Hot, Deficiency/Excess, Interior/Exterior. For example, a sweating herb is used in an acute condition like the flu or a high fever. A clearing herb clears heat from the body and are used in treating infections. Reducing herbs soften and diminish tumors, lumps, cysts or phlegm. Tonifying herbs strengthen various organs and increase vitality. For example, a sweating herb that is cool and acrid is used for high fevers and sore throats. As opposed to a sweating herb that is warm and acrid that is used for secondary flu symptoms such as muscle stiffness that is made worse with cold applications. A tonifying herb that is Qi in nature and is warm and sweet is used for a poor appetite and weight loss. These are just a few examples. There are now 37 different herbal classifications, and this does not include any of the numerous combinations.

Herbal therapy can help an animal as long as the correct dosage and product is prescribed. I recommend that a veterinarian prescribe the correct herbal medication for your animal since they metabolize medications differently than humans.

Equine Gastric Ulcers

Equine gastric ulcer syndrome (EGUS): Separating Fact from Fiction

Benjamin R Buchanan, DVM, DACVIM, DACVECC

Specialist Equine Internal Medicine

Specialist Equine Critical Care

Equine gastric ulcer syndrome (EGUS) is common in performance horses. Depending on the environment up to 90% of horses can be affected. All age and breeds are susceptible and current therapeutic strategies focus on modalities to raise stomach pH. Currently only one approved pharmaceutical agent for the treatment of EGUS exists (Gastrogard^TM Merial). Management strategies are also important in preventing and treating the condition.

The term gastric ulcer most commonly refers to ulceration of the non-glandular mucosa of the equine stomach. EGUS typically includes gastric non-glandular, gastric glandular and esophageal ulcerations.

The equine stomach is unique in anatomy with the proximal third of the stomach lined with squamous epithelium, and the distal 2/3 lined with glandular mucosa responsible for the secretion of pepsinogen and hydrochloric acid. The esophagus is a tube of smooth muscle with non-glandular mucosa connecting the oropharynx to the cardia of the stomach. Smooth muscle in the distal esophagus functions as a “sphincter” or “valve” preventing reflux of acid. Acid induced injury of the esophagus occurs when this sphincter allows acid exposure of the distal esophageal mucosa.

The glandular mucosa is very important in activation and secretion of hormones critical to digestion. The glandular stomach has two types of glandular cells: gastric and pyloric glands. The gastric gland is made up of mucus producing cells, chief cells, and parietal cells. The chief cells produce pepsinogen. The parietal cells produce hydrochloric acid and intrinsic factor. The pyloric glands produce predominately mucus and gastrin.

               

The gastric gland is under the influence of both neural and hormonal signals. Acetylcholine release by the nervous system stimulates the production of both types of glandular cells directly. During digestion gastrin cells release gastrin which stimulates the enterochromaffin cells to produce histamine. Histamine has a direct and profound effect on the gastric gland to release HCl.

Discussion about the development of gastric ulcers focuses on protective and aggressive factors, which are different in the different areas of the GI tract.

PROTECTIVE FACTORS

Protective factors in the glandular mucosa include mucus production, bicarbonate production, and epithelial restitution. The typical pH of this area is 2-3. Because of the constant acid exposure, the glandular mucosa has many anatomical features which protect it from acid injury. Bicarbonate rich mucus production creates an alkaline barrier at the luminal surface. What acid diffuses through this barrier is absorbed quickly buffered and transported away from the stomach by an extensive capillary network. The mucus production and blood flow is regulated by production of prostaglandins.

The protective factors of the esophagus and nonglandular gastric mucosa are limited when compared to the glandular mucosa. There is no buffering capacity from bicarbonate or mucus secretion. Epithelial restitution to repair ulcerated tissue is the primary protective mechanism of the non-glandular mucosa. Buffering of acid in the non glandular area of the stomach is accomplished by salivary bicarbonate and consumption of hay and grass. The typical pH of this area is 5-6.

AGGRESSIVE FACTORS

Aggressive factors for all of the gastric mucosa include exposure to hydrochloric acid, exposure to volatile fatty acids (VFA), pepsin conversion from pepsinogen, and exposure to duodenal reflux of bile. Of these factors the most significant are hydrochloric and VFA exposure. Acid exposure develops during exercise when increased abdominal pressure decreases stomach volume and exposes more of the non glandular tissue to low pH gastric fluid. Frequent exercise of performance horses may be one reason for the increased incidence of nonglandular ulcers found in this group. Exercise may decrease in gastric blood flow and increase serum gastrin which stimulates acid production.

Intermittent feeding or reduced voluntary intake leads to increased acid exposure. When continuous grazing is an option the gastric pH stays elevated (>4) for most of the day. When feed is withheld, gastric pH drops rapidly. Intermittent feeding is one model for creating gastric ulcers and barn management which does not provide hay continuously increases the risk for gastric ulceration. Transportation and stall confinement are the two most common methods of involuntary fasting.

Bacterial fermentation of carbohydrates in the stomach leads to production of volatile fatty acids. These VFAs typically have a pKa of around 4. This means that at pH above 4 they are dissociated and do not penetrate the mucosa. At a pH close to 4 these acids become partially dissociated and lipophillic, and at lower pH they are undissociated, highly lipophillic and able to penetrate the mucosa. Once inside the cell where the pH is elevated they dissociate and alter the intracellular function leading to submucosal swelling and cell death. When combined with an acidic stomach environment the damage is more severe than exposure to hydrochloric acid alone. Lactic acid has not been shown to be synergistic with hydrochloric acid in non glandular ulcer pathogenesis.

Use of nonsteroidal anti-inflammatory drugs (NSAIDs) is often implicated as a major cause of gastric ulceration. They inhibit prostaglandin production which is important for regulation of glandular blood flow and protection of the glandular mucosa. The role of NSAIDs in non-glandular ulcer development is probably overstated as the mucosal blood flow is not a major protective mechanism.

Aggressive factors in the glandular mucosa include all those listed for the non-glandular stomach. Additionally, local bacterial infections have been theorized but never proven to be involved in chronic non-responsive ulcerations of this area. Because the protective mechanisms depend on prostaglandins, the use of NSAIDs (which inhibit prostaglandin production) will cause ulcers in this region.

CLINICAL SIGNS

Clinical signs of EGUS are numerous and often vague. Common clinical signs include refusing grain, partial anorexia, recurring colic, poor performance, and stretching often to urinate. Other symptoms reported to occur secondary to ulcers includes acute colic, excessive recumbency, poor body condition, attitude changes, inadequate energy, and chronic diarrhea.

DIAGNOSIS

Several options are available in diagnosing gastric ulcers. Gastroscopy with a 3 meter endoscope following a 12-24 hour fast allows visualization of the esophagus, non-glandular mucosa, glandular mucosa, and proximal duodenum. Partial gastroscopy can be accomplished with an endoscope of 2.5 meters in most horses. Specialized 3 meter videoendoscopy systems are becoming increasingly common and affordable and are necessary to adequately visualize the pylorus and duodenum.

A newer technique for diagnosing damage to the gastric mucosa is a sucrose absorption test. After sucrose is emptied into the proximal portion of the small intestine, it is rapidly hydrolyzed to its monosaccharide units by the brush border enzyme sucrase-isomaltase; this occurs even in the face of severe small intestinal disease. Any absorption of the intact sugar is thought to occur through defects in the gastric mucosa. The sugar is concentrated in the urine, and increasing concentration is thought to be an indication of ulcer severity. Two techniques have been described. For the original test, the bladder is drained, a dose of table sugar is administered orally, and urine collected two hours later. Recently the test has been modified to a single blood sample 30 to 90 minutes after NG administration of sucrose.

When finances or availability preclude the use of a gastrocope to diagnose ulcers, a tentative diagnosis can be made based on clinical signs, ruling out other diseases, and response to therapy. Clinical signs related to gastric ulcers should abate in 3-4 days after appropriate treatment. However, gastroscopy is often helpful in predicting the length of treatment.

               

TREATMENT

Drug therapy to treat EGUS can be divided into two categories: those that alter gastric pH, and those that alter other factors. To date the only therapy that has achieved positive results in clinical and experimental research are drugs that alter the gastric pH. Such drugs include proton pump inhibitors, histamine type 2 receptor antagonist, and antacids. A Google search netted 30+ pages, and a quick search of the AAEP and ECN list serves found one discussion on ulcer treatment each month for the last two years. However, only therapies that have been published in peer reviewed literature will be discussed here.

               

Proton pump inhibitors prevent the exchange of potassium for hydrogen in the lumen of the gastric gland. Omeprazole is a proton pump inhibitor, and is the standard of care for treating gastric ulcers in the horse. Merial has formulated a paste into 4 gram tubes; Gastrogard^TM. Orally administered Gastrogard^TM at 4 mg/kg will maintain gastric pH >4 for 18-24 hours. Because this is a FDA approved product currently under patent protection, there is no “generic” formulation and compounded formulations are illegal.

               

Additionally omeprazole is not an easy product to force into a solution or paste unless it is dissolved in an acid medium. Using an acid medium for a vehicle shortens the shelf life of omeprazole, which may be the reason for the frequent failures of these products in treatment. Also worth noting is that omeprazole begins to turn dark and/or purple as it loses its potency.

An intravenous form of omeprazole has not been FDA approved for use in horses, but can be legally purchased for administration to horses that are unable to consume products orally. While often cited as being prohibitively expensive, it affordable from certain compounding pharmacies. Recently this product was shown to be effective at suppressing acid production at a dose of 0.5 mg/kg intravenously once daily.

The histamine type 2 (H2) receptor antagonists competitively inhibit the effect of histamine on the gastric glands.  Because the horse has constant acid secretion, the effect of these drugs is dependent on appropriate doses, frequent administration and maintenance of therapeutic levels. A recent study found that 96% of horses in race training on H2 receptor antagonists had evidence of gastric ulcers, most likely due to inappropriate dosing. Ranitidine is the most frequently studied H2 receptor antagonist in horses. At a dose of 6.6 mg/kg PO every 8 hours, it will effectively prevent ulcers in a feed fast model and will inhibit acid secretion. Lower and less frequent doses are not effective. Cimetidine has also been used in horses. Very little research has been done with cimetidine and it does not appear to be effective.

Oral antacids are effective at increasing gastric pH. However, they must be given in large doses and frequently. In a study comparing aluminum hydroxide/magnesium hydroxide and bismuth subsalicylate, only a dose of 30 g of aluminum hydroxide/ 15 g of magnesium hydroxide resulted in a significant increase in gastric pH over baseline or control values. Mean pH was 5.2 +/- 0.62 and 4.59 +/- 0.48 for post treatment hours 1 and 2, respectively.  Each 5 ml of Extra Strength Maalox contains 400 mg magnesium hydroxide, 306 mg aluminum hydroxide and 40 mg simethicone. This means a horse would need almost 100 ml to raise gastric pH for two hours.

Many agents are purchased for the treatment of gastric ulcers that are not acid inhibitors. Many are based on human physiology which target the more uncommon ulcers of the glandular mucosa. Use of dietary rice bran oil had no protective effect on the development of non glandular ulcers in a feed fast model. Corn oil on the other hand, did have a potential protective benefit on the glandular mucosa.

Despite their popularity no other published reference could be found for the multitude of products pushed on clients for treating gastric ulcers.

PREVENTION

There has also been discussion recently on the prevention of gastric ulcers. Because the development of non-glandular ulcers requires constant acid exposure, intermittent inhibition of acid secretion may be preventative. While a 1 mg/kg dose of oral omeprazole may not inhibit acid secretion for 24 hours, when targeted for times of day when there is a high risk of low pH, it may be beneficial in preventing ulcer development. For example giving a 1 mg/kg dose at night when the horse is stalled or not grazing my help horses that do not have turnout or free choice hay all day long. Merial is currently marketing Ulcergard^TM which contains the same amount of omeprazole per tube as gastrogard but is dosed at 1 mg/kg instead of 4 mg/kg.

Another target strategy is to start performance horses on a 4 mg/kg dose of gastrogard a day or two before they ship to a competition and maintain them on gastrogard for the duration of the competition. This will protect the horse from ulcers as it adapts to a new environment and feeding schedule. Prescribing Gastrogard or Ulcergard based on a horse’s risk, may ease some of the financial concerns of the owner. (Table 1)

While the use of drugs is often on everyone’s treatment plan for gastric ulcers, diet and management are also important factors to consider. Addition of alfalfa to the diet has been shown to reduce the number of gastric ulcers seen on endoscopy. Additionally, in vitro, addition of calcium improved recovery of tissue exposed to HCl and volatile fatty acids.

Equine gastric ulcer syndrome is a common problem in performance horses. Understanding the pathophysiology is important in developing rationale treatment and management plans.

TABLE 1 Prevention strategies based on horse’s risk for EGUS

Level of Risk	Husbandry	Diet	Therapy for Prevention
Intense / Race training	Stall confinement	Free choice grass hay and alfalfa. Fed prior to grain.	1-2 mg/kg of Omeprazole PO in evenings
Moderate / Show training	Some pasture turnout	Free choice grass hay and alfalfa when stalled. Fed prior to grain	1 mg/kg of Omeprazole PO in evenings. Alternatively treat with 4 mg/kg Omeprazole PO beginning 3 days before stressful event and continuing for duration of event.
Minimal / Pleasure horse	Complete pasture maintenance	Maintained on pasture	Teat with 4 mg/kg Omeprazole PO beginning 3 days before stressful event and continuing for duration of event.

Chronic Colic in Horses: What to Consider

Chronic Colic in Horses: What to Consider: A horse that colics on a relatively regular basis is a difficult problem for owners and veterinarians alike. Often these bouts of colic pop up unexpectedly with no obvious cause, resulting in frustration for the owner and the diagnosing veterinarian....

The Horse | Equine Protozoal Myeloencephalitis Past and Present

The Horse | <b>Equine</b> Protozoal Myeloencephalitis Past and Present: EPM still frustrates horse owners and veterinarians as one of the most common neurologic diseases in horses....
www.thehorse.com/ViewArticle.aspx?ID=18634

Equine Motor Neuron Disease - Vitamin E Deficiency

Benjamin R Buchanan. DVM. Internal Medicine Specialist, Critical Care Specialist. --

Equine Motor Neuron Disease - Vitamin E Deficiency

With the prolonged drought, heat stressed grass and the anticipated shortness of quality of hay, horse owners should be aware of a uncommon syndrome termed Equine Motor Neuron Disease or EMND.

BACKGROUND: Vitamin E is an important vitamin for the horse. It is a powerful antioxidant essential for normal muscle function. Antioxidants prevent free radicals from damaging cellular membranes and a lack of Vitamin E can lead to muscular problems and neurologic problems. EMND is a well described but uncommonly seen disorder in horses characterized by muscle wasting, muscle dysfunction, muscle fasiculations, and neurologic dysfunction. It develops in response to chronic Vitamin E deficiency (>6 months) which allows oxidative damage to nerves and muscles. The disease affects primarily the motor neurons of the spinal cord ventral horn and brain stem and type 1 muscle fibers. Vitamin E is present in fresh grass, and fresh cut hay but not in dried hay. Additionally diets supplemented with fish or plant oils, and grain that has been stored too long or is rancid may all contribute to a Vitamin E deficiency.

CLINICAL SIGNS: Clinical signs depend on the chronicity of the problem, the age of the horse, and the genetic makeup of the horse. Three forms of EMND are described: 1. subacute, 2. chronic, and 3. subclinical.

In the subacute form of EMND, horses may present for trembling, muscle fasiculations, shifting of weight, abnormal sweating, excessive recumbency, muscle atrophy, and weight loss despite an aggressive appetite. Classically the adult horse exhibits weight loss and neurogenic muscle atrophy first. The gluteal muscles, triceps, and quadriceps are the most affected muscle groups. The muscle atrophy is followed by gait abnormalities and muscle fasiculations, usually within 30 days. Eventually the damage to the postural muscles leads to a abnormal base narrow stance, frequent shifting of weight, a low head carriage, partial prolapse of the penis and/or a slight tail elevation. When moving the horse may appear normal, but the clinical signs will return when the horse stops. Some horses will not stop walking or when forced to stop will lay down. Due to this behavior (trembling and laying down) horses will frequently present to a veterinarian for evaluation of abdominal pain. Ultimately the condition can deteriorate to recumbency.

In the chronic form horses present for poor performance, gait abnormalities, and failure to gain weight. Horses may have gone through a subacute phase, but some horses just develop a chronic form. The horses do not show the same level of trembling and muscle fasiculations as the subacute form. The degree of muscle atrophy may vary from mild to emaciated.

In the subclinical form horses present for performance problems due to low levels of muscle damage.

DIAGNOSIS: Horses affected with EMND frequently have mild elevation of CK and AST. Complete Blood Cell (CBC) counts are normal. A muscle biopsy is the definitive test, but a postural muscle must be sampled. The most frequently biopsied muscle is the sacrocaudalis dorsalis muscle along the tail head. Serum Vitamin E levels may be low or normal. A low Vitamin E with clinical signs is diagnostic, but the disease should not be ruled out based on a normal Vitamin E level. Some horses with EMND will also have an abnormal glucose absorption test although the reasons for and significance of this is not understood.

DIFFERENTIALS: The most important differentials to consider include laminitis, rhabdomyolysis (tying up), and colic. Additionally EPM, PSSM, botulism, and lead toxicity can cause similar symptoms

PREVENTION: Horses being fed poor quality hay with no pasture access should have their Vitamin E levels monitored. Horses that have limited access to pasture should receive at least 2000 IU/day of Vitamin E (dl-a-tocopherol). If this level is not in the grain being fed, or if no grain is being fed, additional supplementation is recommended.

RISK: EMND typically occurs in adult horses beginning around 9 years of age and peaking at 15 years of age. In the few published case series Quarter Horses appear to be at a higher risk.

TREATMENT: Aggressive treatment with oral Vitamin E early in the course can reverse the damage. A water soluble form of Vitamin E should be supplemented based on serum Vitamin E levels. Aggressive supplementation may be necessary for 6 to 8 weeks. Once clinical signs abate and serum Vitamin E levels are normal a lower quality or lesser amounts of Vitamin E can be supplemented. In addition to Vitamin E supplementation, acutely affected horses will need supportive care.

PROGNOSIS: The prognosis depends on the level of damage. Severe cases may not ever return to the same level of performance. Slightly less than half of horses with the subacute or chronic form treated will regain all muscle mass and return to normal function. Many horses will stabilize but will not regain the muscle mass lost without appropriate rehabilitation. A low percentage of horses will continue to deteriorate despite treatment.

REFERENCE: Reed, Bayly, Sellon editors. Equine Internal Medicine 3rd edition. Pages 521-522 and 634 - 637.

Acupuncture

Dr. Shana Buchanan will be seeing appointments the second and fourth Monday of every month at BVEH in Navasota. She is a veterinarian specializing in Acupuncture, Chiropractic, Food Therapy, and Herbal Therapy.

Acupuncture:

As you recall, TCVM includes acupuncture, herbal medicine, and food therapy. Additionally, TCVM recognizes patterns of disease and imbalance in the body, and the treatment is to bring the body back into balance, or homeostasis. Since TCVM deals with energy, it does not identify diseases the same as Western Medicine. Identification of patterns of disharmony is accomplished through examination, tongue and pulse diagnostics, and history. The treatment plan is then formed in order to bring the body back into homeostasis. Acupuncture is an excellent method of bringing the body back into balance. Acupuncture point stimulation is used to stimulate the body’s intrinsic healing mechanism in order to restore vitality. Furthermore, acupuncture not only deals with the internal problems but the external environmental factors that influence the body. In contrast, Western Medicine tries to replace deficiencies and does not examine the external environment. This is why an integrative approach of using both TCVM and Western Medicine can help the body heal quicker with fewer side effects.

As stated previously, acupuncture deals with energy, Qi, and the body’s natural ability to heal itself. The term acupuncture derives from the Latin words: acus meaning needle and pungare meaning to pierce. Acupuncture is performed by placing small, solid, metal needles into specific locations in the body, acupuncture points, to prevent and treat disease. After inserting needles the needles can either be left in place for a particular amount of time, have moxa, or mugwart, burned on the tips, or have electrodes connected to stimulate the area, similar to a TENS unit.

How do we know where acupuncture points are located and their uses? Acupuncture points have been studied for over 3,500 years. Therefore, the points that are used have been thoroughly researched and anecdotally proven through centuries of evidence. It is believed that each acupoint communicates with a specific organ and reflects the conditions of that organ or meridian. When the organ or meridian has changes, the related points may become sensitive or show altered signs such as cold or heat. The stimulation of each point by acupuncture can reach the related organ via the point and the meridian. When scientists dissected acupuncture points, it was discovered that the majority of points had an associated artery, vein and nerve. For the main artery, vein and nerve groups it was recognized that these groupings were TCVM Master and Influential Points of the body. The smaller groupings have influential affects on the body but at a smaller scale. There are some points on the body that do not relate to definitive acupuncture points. These points are called “Trigger Points,” or “Ahshi Points.” Ahshi points are sensitive, nonspecific acupoints that reflects pain or abnormalities associated with that certain part of the body. Therefore, an acupuncture treatment will consist of points for the organ, the meridian, and local points that are identified.

The big question is what can acupuncture treat? In my opinion, most, if not all diseases, should have an integrative approach of treating the animal with TCVM and Western Medicine. The animal will only benefit by this dual modality. Additionally, this modality does not have to be an even split between the two methods but a cognizant approach to the animal. There will be times that a patient’s environment, weight, and activity level needs to be addressed before, during and after the treatments in order for acupuncture to be efficacious and have favorable outcomes. Additionally, acupuncture treatments will occasionally not produce the desired effects as a result of the disease process. Here is a brief, and incomplete, list of acupuncture treatments:

• Analgesia, analgesia, analgesia!!


• Neurologic Disorders: nerve growth stimulation and trauma recovery


• Emergency Medicine: respiratory arrest, shock, CPR


• Cardiovascular Disease: blood pressure, arrhythmias, heart failure


• Chronic Respiratory Conditions: chronic obstructive pulmonary disease (COPD), asthma, acute/ chronic upper respiratory disease, allergic and infectious tracheobronchitis


• Gastrointestinal Disorders: motility, gastric ulcers, nausea and vomiting, diarrhea, abdominal pain


• Reproductive Disorders: anestrus, cystic ovaries, impotence, abortion/dystocia, retained placenta, uterine prolapse, post operative spay/castration analgesia


• Immunologic Disorders: FIV, feline lymphocytic-plasmacytic gingivitis, inflammatory bowel disease (IBD), immune-mediated joint disease, feline bronchial disease


• Dermatology Disorders: pyoderma, anal sac disease

In conclusion, acupuncture is a treatment modality that will only benefit the animal by correcting the problem, relaxing the pet, and bringing the body back into balance. The best aspect of acupuncture is that you cannot overdose the animal since this is typically a benign form of treatment. Acupuncture cannot change conformation, heal fractures, nor make neoplastic growths resolve as a sole treatment modality. However, acupuncture can alleviate certain problems associated with structural issues or secondary problems associated with diseases of the body.

Tetanus

Tetanus:Vaccinations can help protect your horse.

From AQHA Coporate Partner Pfizer

All horses are at risk for developing tetanus. This is why a good vaccination program is so important. Journal photo.

As American Quarter Horse owners, there are a number of diseases to keep an eye out for and help protect your horse against, such as West Nile virus, Eastern and Western equine encephalitis, rabies, strangles and tetanus. The good news is that tetanus, like the other core diseases, is preventable through a veterinarian-administered vaccination program.

All horses can be at risk for developing tetanus, an often-fatal disease caused by a toxin produced by Clostridium tetani, a spore-forming bacterium present in the digestive tract of many animals and in the soil¹. Spores of Cl. tetani can survive in the environment for many years, resulting in an ever-present risk of exposure in horses at equine facilities. Tetanus is not a contagious disease but can be the result of the Cl. tetani toxins entering the horse’s body via puncture wounds, open lacerations, surgical incisions or exposed tissues in unvaccinated horses².

“Tetanus vaccines are very effective,” said Dr. Tom Lenz, senior director of equine veterinary services for Pfizer Animal Health. “However, your horses won’t be protected if they are not vaccinated.”

Your horse’s health is important to you. To stay on top of it and keep up-to-date on health information, check out our Common Horse Health Issues report. You’ll find information about strangles, West Nile virus, colic, laminitis, EPM and more!

If tetanus is left untreated, it can be fatal. According to Dr. Nat T. Messer IV, professor in equine medicine and surgery at the University of Missouri College of Veterinary medicine, “’usually 50 to 75 percent of the horses that get tetanus will succumb to the disease, no matter what is done to treat them’”¹.

Wounds and Tetanus

Wound contamination typically leads to infection, as a well-cleaned wound is not likely to result in tetanus. Rather it is usually a wound that contains foreign matter such as soil¹.

The incubation period for tetanus is usually one to three weeks. Spores can lie dormant in tissues after wound healing and produce toxins if the local oxygen level drops¹. Much of the progression and outcome of this disease depends on how much toxin makes it to the spinal cord¹.

Clinical Signs

Tetanus affects the central nervous system of the horse. Once the toxins reach the central nervous system, they stimulate the muscles to extend, and the characteristic muscle spasms begin¹. Some of the early indications may include a stiff gait, a raised tail or the horse being reluctant to move.

When the muscles are in spasm, the head and face contract, producing a classic facial expression with ears erect, nostrils flared and a sardonic grin — the muscles of the lips are pulled back like the horse is smiling, showing his teeth¹.

The disease is commonly known as lockjaw, because the jaw muscles become rigid and the horse can’t eat and has difficulty swallowing.

Due to the neurological symptoms such as the stiffness and muscle rigidity, it is important to have a proper diagnosis from a veterinarian, as the disease could be confused with other neurological diseases such as EPM, botulism or rabies.

It’s always important to be prepared for any kind of medical emergency. Let AQHA help with our Common Horse Health Issues report. It will help you learn more about common health issues horse owners face.

Prevention

Proper vaccination by a veterinarian is the best way to help protect a horse from tetanus. Vaccines are currently available with inactivated, adjuvanted tetanus toxoids. Tetanus toxoid vaccines administered per manufacturer recommendations are both safe and effective².

Pfizer Animal Health offers a TETANUS TOXOID and a TETANUS ANTITOXIN .The TETANUS TOXOID is offered in combination with the INNOVATOR® lines of vaccines including WEST NILE-INNOVATOR® or FLUVAC INNOVATOR®.

According to the American Association of Equine Practitioners vaccination guidelines, tetanus is considered a core vaccination. Core vaccinations are those that help protect against diseases that are endemic to a region and that have potential public health significance³. Core diseases include Eastern equine encephalitis, Western equine encephalitis, West Nile virus and rabies. Due to the variations of vaccines on the market, it is important to consult a veterinarian when developing a vaccination program.

If you suspect that a horse has tetanus, notify a veterinarian to confirm the disease.

References

1. Thomas, Heather Smith. Tetanus in Horses. November 1, 2009. Available at:

http://www.thehorse.com/ViewArticle.aspx?ID=15276. Accessed August 2, 2011.

2. Tetanus American Association of Equine Practitioners. 2008. Available at:

http://www.aaep.org/tetanus.htm. Accessed on June 13, 2011.

3. Core Vaccination Guidelines. American Association of Equine Practitioners. 2008. Available

at: http://www.aaep.org/core_vaccinations.htm. Accessed on June 13, 2011.

Endoscopic evaluation of the navicular bursa: Observations, treatment and outcome in 92 cases with identified pathology

Endoscopic evaluation of the navicular bursa: Observations, treatment and outcome in 92 cases with identified pathology:

Summary

Reasons for performing study: Diagnostic navicular bursoscopy has been described in limited cases. Review of greater numbers is needed to define its contribution to case management and prognostic values.

Objectives: To report: 1) clinical, diagnostic and endoscopic findings in a series of cases, 2) surgical techniques and case outcomes and 3) prognostic values. The authors hypothesise: 1) lameness localising to the navicular bursa is commonly associated with dorsal border deep digital flexor tendon (DDFT) lesions, 2) endoscopy allows extent of injuries to be assessed and treated, 3) case outcome relates to severity of DDFT injury and 4) the technique is safe and associated with little morbidity.

Materials and methods: All horses that underwent endoscopy of a forelimb navicular bursa for investigation of lameness were identified. Case files were reviewed and those with injuries within the bursa selected for further analysis.

Results: One-hundred-and-fourteen horses were identified. Ninety-two had injuries within the bursa and DDFT injuries were identified in 98% of bursae. Of those examined with magnetic resonance imaging (MRI), 56% had combination injuries involving the DDFT and navicular bone. Sixty-one percent of horses returned to work sound, 42% returned to previous performance. Horses with extensive tearing and combination injuries of the DDFT and navicular bone identified with MRI, had worse outcomes.

Conclusions: Lameness localising to the navicular bursa is commonly associated with injuries to the dorsal border of the DDFT. Endoscopy permits identification and characterisation of injuries within the navicular bursa and enables lesion management. Outcome following debridement is related to severity of injury but overall is reasonable.

Potential relevance: Horses with lameness localising to the navicular bursa may have tears of the DDFT. Bursoscopy is able to contribute diagnostic and prognostic information and debridement of lesions improves outcome compared to cases managed conservatively.

West Nile Virus Confirmed in Texas Horses

Even with no rain, there are still mosquitoes. Given the Eastern Encephalitis problems they are experiencing on the East Coast, it is prudent to make sure your horse's are up to date on WNV and EWT. West Nile Virus Confirmed in Texas <b>Horses</b>: The 2011 mosquito-borne disease season is in full swing as two Texas horses have tested positive for West Nile virus (WNV) in two different counties. Jim Schuermann, staff epidemiologist for vectorborne and zoonotic diseases of the Zoonosis Control ...
See all stories on this topic »

Alternative Veterinay Medicine

BVEH in Navasota, is pleased to announce a new partnership with Dr. Shana Buchanan. Shana is a veterinarian trained in many aspects of alternative veterinary medicine including acupuncture, chiropractic, food therapy, and herbal medicine. We are working out a regular schedule for her to see patients at the clinic and will publish that soon. Shana has also started writing a blog and we will post those as we receive them, or you can read them by becoming her fan on facebook (http://www.facebook.com/pages/Alternative-Veterinary-Care-Specialties/142250842529644).

Alternative Veterinay Medicine: "

TCVM has been used to treat animals in China for thousand of years. TCVM was developed by trial and error in order to understand domestic animal diseases. This process began in the pre-historic times to the present day while continuing to grow with the incorporation of new information through the generations, similar to Conventional Western Medicine. Chinese Medicine, or Eastern Medicine, believes in balance and energy, and practitioners recognize animal diseases as an imbalance in the body. The body is an integrated, energetic structure and a disturbance of energy flow creates disease processes in the entire organism. When a disease pattern is identified, TCVM can restore balance and health by helping the body regulate itself. Diagnostic tests of TCVM include pulse palpation, tongue evaluation, specific acupuncture point palpation, and history. The aspects of TCVM include: Yin and Yang, Meridians, Qi, Zang-Fu Organs, and Five Elements.

Yin and Yang is symbolized by the above Tai diagram. This symbolizes harmony in the universe. The circle represents the universe and is equally divided into Yin (black and female) and Yang (white and male). They are continuously merged since a small circle of Yin is within Yang and vice versa. The Yin descends to nourish Yang, and Yang rises to support Yin. Yin and Yang compose and divide all things yet they cycle unceasingly in the state of eternal transformation.

The Meridians are pathways by which Qi and Blood circulate throughout the body. The pathways are not physically visible. However, they unify all parts of the organism, connecting the internal organs with the external body, thus maintaining harmony and equilibrium. Along each meridian, there are special points called acupuncture points. These specific points are used as acupuncture diagnostic points and treatments for diseases.

The Qi is the force or energy that controls the harmony in any living body. Qi has been referred to as the vital force or life energy that activates and maintains the life process. Most of the Qi can be replenished from proper nutrition, regular exercise, and the environment. Certain types of Qi cannot be replenished since they are only formed during conception. TCVM manipulates and regulates Qi flow through the Meridian channels.

The Zang-Fu Organs are the internal organs that are Yin or Yang. An animal’s health depends upon the function of these organs. The Fu, or Yang, organs are hollow organs of the body. Fu organs function to absorb nutrients and eliminate waste products. The Fu organs are the stomach, small intestines, large intestine, gall bladder, bladder, and triple heater. The Zang, or Yin, organs are solid organs of the body. Zang organs process the absorbed nutritive substances and store the metabolic products. The Zang organs are the liver, spleen, kidney, heart, lung, and pericardium. Each of the Zang-Fu organs is represented by the Meridian system on the external portion of the body.

The five elements involved in TCVM are the elements of the natural world. The elements are Metal, Water, Wood, Fire, and Earth. The Zang-Fu organs are categorized by these, and therefore, the elements describe the nature of the Zang-Fu organs with their inter-relationship between the body and the natural world. The five element theory helps veterinarians in the clinical diagnosis of disease and disease treatments.

TCVM veterinarians help regulate the balance of the body by influencing the Yin and Yang, the Qi, the Meridians, and the Zang-Fu organs of the body. First, this is accomplished by performing acupuncture on a weekly basis for 6-8 weeks, then gradually decreasing the frequency to the most effective level. A second method of regulating the body balance is by herb therapy. Herbs should be given in combination with acupuncture treatments and not alone and should only be prescribed by a veterinarian. A third method of regulating the body’s balance is by food therapy. Different foods contain certain properties that will help the body heal and prevent diseases. However, food therapy for veterinary patients should be explored with caution. Veterinarians should perform acupuncture treatments and prescribe herbal and food therapies for veterinary patients. All animals can benefit from TCVM treatments, and I believe that an integrative approach of incorporating Western and Eastern Medicine will have maximum benefits for the patient.

References

Schoen, A. (2001). Veterinary Acupuncture: Ancient Art to Modern Medicine (2nd ed.). Missouri: Mosby, Inc.

Schwartz, C. (1996). Four Paws Five Directions: A Guide to Chinese Medicine for Cats and Dogs. California: Celestial Arts Publishing.

Xie, H & Preast, V. (2002). Traditional Chinese Veterinary Medicine: Volume 1 Fundamental Principles. Florida: Jing Tang.

Xie, H & Preast V. (2007). Xie’s Veterinary Acupuncture. Iowa: Blackwell Publishing.

"

Is Your Horse's Bit Harmful to His Mouth?

I thought this was interesting. There are some relatively simple ways to examine the horse's bars for pain and is part of the lameness work-up/poor performance exam at BVEH.

Is Your Horse's Bit Harmful to His Mouth?: "When behavioral problems arise with riding horses, owners undoubtedly will search for solutions. But many horse owners don't think to look their horse in the mouth for an answer. According to recent study results, the bit could be the cause of more ...

"

Colic in Horses: When is Surgery Necessary?

I thought this was a nice summary of the process we go through when evaluating your horse. It is always our goal to avoid surgery when it is not needed, but delaying surgery when it is indicated can be fatal. - Ben Buchanan

Colic in Horses: When is Surgery Necessary?: "When a horse is in the midst of a bout of colic, an owner might wonder if his or her animal will need surgery to fix the problem. For those owners whose horses have never been referred to an emergency medical clinic for surgery or intensive care ... ...

"

Supporting Limb Laminitis: Prevention is the Best Treatment

Supporting Limb Laminitis: Prevention is the Best Treatment: "When your horse suffers a major injury, such as a severely broken bone in a leg, the last thing you might be thinking about is laminitis. But laminitis should certainly be on your radar, as many horses that suffer serious limb or hoof injuries develop supporting limb laminitis, a condition that can prove fatal even if the original injury is well on its wa..."

Associations between the Exposure to Airborne Virulent Rhodococcus equi and the Incidence of R equi Pneumonia among Individual Foals

Associations between the Exposure to Airborne Virulent Rhodococcus equi and the Incidence of R equi Pneumonia among Individual Foals: "Abstract: Rhodococcus equi is a significant cause of pneumonia, resulting in disease and sometimes death of foals. It is believed that infection occurs by inhalation of dust contaminated with virulent R equi. Although association between the airborne concentration of virulent R equi and the incidence of foal pneumonia at breeding farms has been documented, studies at the level of individual foals have not been reported. Thus, the objective of this study was to determine whether the magnitude of airborne virulent R equi was significantly associated with risk of R equi pneumonia for individual foals. The concentration of virulent R equi was significantly (P < .001) greater in stalls than paddocks among samples collected from 47 foals at a breeding farm in central Kentucky. The presence of airborne virulent R equi in stalls was significantly (P = .045) more likely at 7 days of age for foals subsequently found to be affected by rhodococcal pneumonia. Additionally, airborne concentrations of virulent R equi in stalls were significantly greater at 7 and 14 days of age than at birth. Presence of the mare and foal at the time of sampling was significantly (P < .001) associated with increased airborne concentrations of virulent R equi in stalls. These findings suggest that environments containing airborne virulent R equi during the first week of life may influence the risk of subsequent disease for a foal."

Wobbler Syndrome in Horses: An Overview

Wobbler Syndrome in Horses: An Overview: "There are few things more enjoyable than watching a herd of young horses frolic around a pasture. But when one of the foals looks shaky, incoordinated, and almost wobbly on his feet, this could be a sign of a serious--and sometimes fatal--neurologic problem: cervical vertebral stenotic myelopathy, or wobbler syndrome. At the 2011 Western Veterinary Confer..."

Horsekeeping in a Trying Economy

In these difficult economic times, it is tempting to cut corners in horsekeeping costs. One hundred twenty five dollar dental floats, $150 shoeings, $100 vaccinations sessions - they all add up. However, costs should not be cut when it bring risk to your horse’s health.

It is possible to save money without compromising the well-being of your horse. Many of these measures may help to improve his health, resulting in savings in the long run.

Vaccinate

Vaccinations prevent disease, and though it may seem spendy to administer routine inoculations, it is much cheaper than treating the resulting illness or the ultimate cost: your horse’s life. Cases of Eastern Equine Encephalitis (EEE) have recently turned up in Texas and rabies is always a threat. Tetanus is a constant problem around the stable.

If you are comfortable doing so, save money by vaccinating the horse yourself. There will be some vaccines which you will need to obtain from your vet, like Rabies, but vaccines are a generally simple procedure that many horse owners are comfortable administering.

Depending on your horse’s hauling schedule, he may not require a full set of vaccinations. Horses which are heavily hauled will need a different series of vaccinations than ones stabled in a closed herd. Work with your vet on a sensible program to fit your herd. For further information, please see BVEH’s 2009 Winter Newsletter on general horse care.

Increase Forage

Feed as much forage as you can and cut back on the grain. Good quality hay and pasture is the healthiest and cheapest diet. Evaluate your horse and what his maintenance needs are. Assess his energy needs – does he really need 12 quarts of grain per day if he is ridden once a week? You may be able to decrease or eliminate grain altogether. Feed representatives or your vet will be able to assess nutritional needs and guide you towards a feed program to fit your budget.

Pasture 24/7

Not only will considerable amounts of money be saved on bedding, stall repairs and labor, it is healthier for a horse to be turned out constantly. The horse is able to breathe fresher air, which can in turn decrease Recurrent Airway Obstruction (heaves – see BVEH 2008 Summer Newsletter for further information). There is more room to move, which may help prevent legs from stocking up or any stiffness which may occur when the horse is stalled up. Just be sure there is access to some type of shelter (stall, lean to, etc…) for the horse to escape inclement weather, though you may find the horse is content to stand outside in it.

Water

Water is the cheapest and most important nutrient you can provide for your animals. In freezing temps, make sure there is still an accessible supply. Don’t assume your horse can keep a drinking hole open faster than a bucket, trough, or pond can freeze over. Consider a heating element if temperatures will be below freezing for long periods at a time. If you are concerned your horse may not consume enough when it is cold, try adding a tablespoon or two of salt to his grain ration to entice drinking.

Deworming

Deworming every eight weeks just to deworm can be a costly venture. Rather, have your vet perform a fecal egg count which will aid in targeting treatment for specific parasites. See BVEH 2009 Winter Newsletter for more information.

Tend to Minor Issues

Correct minor problems before they escalate into major ones. Teeth floating, proper shoeing and farrier work, colics and wound treatment can be handled in early stages before they turn into full blown problems. Haul your horse to the clinic to avoid a farm call charge.

Horses are expensive to purchase and upkeep. By evaluating your program as a whole, a budget can be created and implemented to keep expenditures at a minimum. There are certain areas where corners should not but cut, but by eliminating unnecessary expenses, horse owners will find there are plenty of ways to cut costs without compromising horse health.

If, after cutting back, you find you still cannot afford to keep your horse, consider the following options:

• Sell your horse
• Lease or loan it out
• Decrease the amount you show or haul
• Remove him from the trainer and consider pre-show-week tune-ups only
• Donate to a therapeutic riding program
• Donate to a university for riding, research, vet school

The latter may be an extremely heartbreaking decisions, but for very old, crippled, or chronically ill horses which may not be able to find another home, the best thing for the horse might be to say good bye. Pet cemeteries offer horse burial and marker placement, commemorating the horse’s life and the joy it brought to yours.

PSSM

PSSM

Polysaccharide Storage Myopathy (PSSM) is an inherited, debilitating condition related to tying up. It is caused by a sugar imbalance in which even light exercise can lead to cramping.

Normally after exercise, a horse will slowly absorb glucose from the bowel to replenish metabolized glycogen (sugar in the muscle) until normal resting levels are achieved. Horses with PSSM experience an increased sensitivity to insulin, resulting in overcompensated storage of glycogen in their muscles, up to twice the normal level.

As glycogen builds up, pain is brought on as a result of disrupted muscle fiber function. Frequently, this pain is found in the back, both along the epaxial muscles (muscles on both sides of the back) and in the longissimus dorsi, found in the sacrum.

Signs of PSSM will generally occur early in the training session. In addition to pain, there may be stiffness and cramping, poor performance, muscle weakness and atrophy, or even behavioral changes. To alleviate cramping, male horses may stretch as if to urinate.

The typical PSSM horse will be calm and well muscled but usually not fit. PSSM is found more frequently in Quarter Horses, warmbloods, and drafts, with Quarter Horses appearing to have earlier onset of PSSM in comparison to other breeds.

Conformation is made through a muscle biopsy. The biopsy will grade as mild, moderate, or severe. There is currently research being conducted on testing which will be able to utilize genetic markers to diagnose PSSM, but for the time being muscle biopsy is the only channel of diagnostics. Muscle enzymes may be evaluated but do not always indicate the presence of PSSM.

Horses diagnosed with PSSM will be placed on a strict diet consisting of low sugar, low starch, and high fat. Fat, such as rice bran, helps muscle cells take up less glucose. It is best to feed these horses small meals several times a day to alleviate surges of blood glucose.

In addition, the horse should be turned out as much as possible. Confinement may lead to elevated levels of creatine kinase, especially when the horse is exercised, placing the horse at risk for a full-scale episode of ER. Exercise should be gradually increased to allow the horse to adapt to the demands and the horse should be exercised often, even if only for 10 minutes per day.

Any performance horse with back pain should be evaluated for PSSM. There is a favorable improvement rate (around 80%) seen in horses with mild to moderate PSSM and many of them return to full competition. Owners need to realize there may always be some risk for muscle soreness but with a vigilant management program this disease is quite controllable. As with ER, is may take weeks or even months to discover the success of a treatment plan.

Rhodococcus Equi

Rhodococcus Equi

Rhodococcus equi (R. equi) is a bacteria responsible for causing severe pneumonia in foals, leading to significant losses to the industry on a yearly basis.

Pneumonia is quite common in foals and a chief cause of illness and death in this population. Casualty rates of horses affected with R. equi are high - nearly 28%. In addition to economic loss from mortality, future athletic performances from recovered horses may be in peril as well.

R. equi bacterium live in the soil and feces of hervibores. The bacteria relies on warmth and nutrients found in manure to grow and it is unknown how long it can survive in this environment. Survival in the soil can last as long as one year. Some farms appear to be predisposed to this bacterium and more frequent occurrences, up to 20% of their foal population, are seen. 

Most foals are exposed but only some develop symptoms. It is unclear why, but likely this is due to immune status, environmental factors and farm management.

Foals become infected when they breathe bacteria in the soil, dust or feces. These bacteria multiply inside macrophages (white blood cells that normally kill bacteria) and can cause lung abscesses, which lead to pneumonia. Other conditions can also develop including osteomylitis (bone infection), neonatal diarrhea, lymph node inflammation, spinal cord abscesses, immune mediated diseases (purpura hemmorhagica, for example) and sudden death in an otherwise healthy foal.

Foals are believed to become infected when they are less than two weeks old but clinical signs are not obvious until they are one to three months old. It is an accepted belief that R. equi can cause pneumonia in foals up to six months of age.

Clinical signs develop rapidly. Horses will exhibit a thick, greenish white mucopurulent discharge from the nostrils, fever, and lethargy. Respiratory issues such as an increased breathing rate, crackles, and wheezes will be present as well.

The veterinarian will have to work to differentiate R. equi from other causes of pneumonia, including bacteria or fungal respiratory infections. This is not an easy disease to diagnose, especially early on. Diagnosis is usually obtained through thoracic radiographs, ultrasounding the lungs and also via trans tracheal wash. Routine bloodwork alone is not specific enough to confirm a diagnosis. Elevated white cell and fibrinogen counts will only indicate general infection or inflammation.

Treatment is expensive, time consuming (the horse will need to be treated several times daily) and can come with serious side effects. Early detection is vital. Antibiotic therapy utilizing erythromycin, rifampin, and clarithromycin work to penetrate the lung abscesses and macrophages where bacteria multiply. Complementary therapy of yogurt and/or Amaferm Recovery Paste should be added to treatment to ward off potentially fatal diarrhea. Watch for any signs of foal hyperthermia as well.

Treatment should be at minimum four weeks, and oftentimes needs to continue up to eight weeks. It should continue until lung scans and fibrinogen return to normal.

BVEH recommends an initial lung scan for at-risk foals beginning at 30 days of age, then continuing every 30 days until the foal is six months old.

R. Equi is difficult to control but good farm management and stringent hygiene protocols can minimize infection. Keeping foals on grassy pastures and frequently removing manure can significantly reduce the risk.

The only prevention for R. equi is to administer a specially prepared plasma, which is costly and unfortunately, not 100% effective. Treatment should begin shortly after birth, with a second treatment to follow 30 days later.

Horse to human transmission can occur, however the disease can only occur if the person’s immune system is severely compromised.

In a study conducted by Texas A & M University, researchers discovered that increasing the amount of foals per acre seems to correlate with an increased risk factor of R. equi. In addition, it was found farms with large populations of mares and foals, or large numbers of transient mares/foals had increased incidence of R. equi. It has been thought prophylactic azithromycin for the first two weeks of life may prevent bouts of R. equi, but unnecessary use of antibiotics is frowned upon and further research is needed to investigate the accuracy of this claim. 

Spring/Summer Skin Problems

The skin is the largest organ on a horse, accounting for roughly 18% of its body weight. While the skin is susceptible to an assortment of maladies year round, several are most prevalent during the springtime rainy season. Skin inflammation, or “dermatitis”, is an all inclusive term for aggravated by external irritants, burns, allergies, trauma or infections (bacterial, viral, parasitic or fungal). Dermatitis can be a systemic disease as well.

The most common sign is scratching followed by redness, swelling, and appearance of bumps. It progresses to oozing, crusting, or scaling lesions. Any suspected skin condition should be addressed by your vet as it is important to determine the cause. Diseases can appear the same but treatment can be very different and a proper diagnosis and treatment can save time, money, and the intensity of the condition.

Scratches

Scratches are also referred to as pastern dermatitis, dew poisoning, greasy heel, or mud fever. It is not a condition but rather a description of a problem seen on the lower limbs. It can be viral, bacterial, fungal or parasitic. Risk of contracting this condition increases if the horse is in wet or muddy conditions. Those with light or white skin seem to be more susceptible.

The skin may appear itchy, flaky, sensitive or swollen. Chronically infected horses may have granulomas present.

Treatment should begin as soon as possible. Be gentle, as the area may be sensitive. The best treatment is to keep the skin dry. Remove the horse from the wet area or mud, clip the surrounding hair, and wash the area with an antibacterial soap or Betadine scrub daily. Thoroughly towel dry the area.

Do your best to keep the horse out of the wet and out of tall grass during and after treatment. Stall him up, keep him in a covered arena, or bandage the affected area, using Corona or a diaper rash ointment to keep water out, preventing spread. Resist the urge to pick any scabs which may be present. They should be soaked or sweated off.

Severe cases require application of an antibiotic or antifungal ointment and dexamethasone therapy.

Be diligent about disinfecting boots, wraps and grooming equipment.

Thrush

Thrush is a common infection of the hoof that usually affects the tissues of the frog adjacent to the sulci (deep grooves).

It is a common misconception that thrush is only caused by dirty or unkempt environments (which it can be), but in fact thrush can and does occur in the cleanest of conditions.

There is a myriad of elements causing thrush, including abnormal hoof growth, poor shoeing, poor diet/exercise, chronic lameness issues, or poor frog circulation – basically anything that disrupts the horse’s built in cleaning mechanism.

The process of a horse’s hoof cleaning itself can be seen when the limb supports weight. The sole normally becomes flat and the coffin bone descends upon it and expands the frog. This in turn flushes out any substances which may lie in the sulci. Problems begin when the debris are not removed.

Diagnosis is fairly easy –a thick, black, putty-like, foul-smelling material is seen on the frog and in the suici.

This infection is generally easy to manage at home, after a blacksmith or vet trims any dead tissue from the area. The affected foot should be picked out and cleaned daily and any number of topical remedies may be applied, either commercial or homemade.

Over the counter products like Thrush-X or Kopertox and homemade topicals can be applied, including a bleach/water solution (not recommended, as it can often affect healthy tissue), or Sugardine (table sugar mixed with Betadine to form a thick paste).

There are a variety of ways to apply the medication – medicate the hoof and keep it dry, soak the affected hoof in a bucket, tub or medication boot, or, if the horse absolutely cannot be kept out of the wet (or if it is a severe case), soak gauze with the treatment of choice, pack it into the hoof, and wrap. Leave it on 1-3 days before removing. Repeat if necessary.

It is important to involve the vet when treating thrush in order to identify the cause, especially if several horses are affected or one horse becomes chronically affected.

While not a common side effect, thrush can cause permanent lameness if it invades the white line, sole and sensitive tissues. However, most of the time prognosis is excellent with meticulous care of the hoof. Keep the feet picked out and the frog healthy and begin treatment as soon as thrush is suspected.

Rain Scald

Rain scald/rain rot is a dermatitis that affects horses, cattle, sheep, goats and even humans. It can be acute or chronic but is most commonly seen after rainy weather. Infected animals are considered the primary carrier of this bacteria, and it is believed the infection is triggered when the skin is compromised, as in the case of prolonged wetting, increased humidity, high temperatures or insects. Heavy rainfall softens superficial layers of skin and allows an easier path for infection. Natural immunity is hereditary.

Frequently, lesions are seen on the rump, loin, and saddle area. These lesions appear like large drops of scalded skin and often involve the legs.

Exudate (fluid) mats hairs together in plaques (clumps). The actual plaque is small (1mm – 2 cm) but may cover large areas. These clusters will clump out and may have a paintbrush affect in appearance.  These plaques can be tender to the touch and when removed, a moist, pink, bleeding lesion is revealed.

The exudates may appear as a yellowish-green pus, or gray and gelatinous in texture.  Older lesions may be painful where scabs were removed.

A tuft of hair matted at the base to form a scab covered with exudate is highly indicative of rain scald. Positive diagnosis is determined through culture and/or laboratory examination of the cluster.

Clusters can be potent for an extensive length of time (up to 42 months). Disinfection of equipment and facilities is crucial as well as proper disposal of any crusts, as rain scald is easily spread via contaminated clippers, grooming equipment, or wet lesions. Ideally, these crusts should be incinerated.

Lesions which are dry, hard and cracking respond well to antibiotic or steroid topicals like neomycin or hydrocortisone.

The horse should be bathed with a special iodine shampoo, lime sulfur, or chlorhexadine bath for several days prior to crust removal. A diluted mineral oil can be sprayed on to soften crusts and aid in removal. Many horses recover spontaneously in four weeks.

Unlike ringworm, rain scald is not itchy. The best cure is sun and dry weather. Severe or chronic cases should be treated with antibiotics such as penicillin or streptomycin.

Researchers are still working to determine if bacteria responsible for rain scald live in the soil.

Ringworm

Ringworm is not a worm at all; rather it is a fungal infection seen in warm, damp, dirty or poorly ventilated conditions. The fungus causes skin inflammation when toxins are introduced and the horse experiences a hypersensitive reaction. It is transmissible to humans.

Horses contract ringworm by direct contact with an infected horse, person, soil or equipment. Rodents have been known to transmit this condition as well. Younger or older horse populations, as well as those who have suppressed immune systems, been on prolonged antibiotics or immunosuppressive therapy appear to be predisposed to this condition.

Typically, multiple areas of scaly, crusty patches of hair loss spread (mainly where tack contact is – i.e. girth area), usually in a circular pattern. It is also seen on pasterns.

At first, the lesions may resemble fly bites and can be painful. They may keep expanding for 4-8 weeks and retreat as immunity develops.

The affected area should be clipped and topical treatments applied. Treatment with oral medication griesofulvacin for 30-60 days is recommend. Lime sulfur baths can be beneficial.

Horses should be isolated to prevent transmission and these horses need to be handled after handling all others. Careful cleanup should occur after contact, as human transmission is possible.

Set aside separate saddle pads, girths, bandages and bathing tools for these horses during outbreaks.  As with other easily transmissible disorders, all equipment, feed and water tubs should be thoroughly disinfected.

Prompt Action

The best treatment for skin afflictions is prevention, and if an affliction is diagnosed, prompt attention to deal with it. Any skin issues should be immediately addressed. Involve your vet to prevent wasting time or money on incorrect treatments and to prevent escalation within the single horse and also to the herd. 

Treat the horse with your choice of topical daily for five to seven days, then weekly to keep future outbreaks in check.

Skin conditions, while usually not complicated, can quickly intensify and/or progress to other animals in the herd. Good management practices, along with a watchful eye, can halt skin conditions before they get out of hand.