| When the Chips Are Down |
October/2006 |
In the case of bone chips, sometimes bigger is better. In a study performed in 2006, researchers from the University of Pennsylvania's New Bolton Center theorized that bone chip characteristics in a horse's knees were an indicator of the severity of the horse's injury. They were right.
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| NSAIDs: Not All They're 'Stacked' Up To Be |
September/2006 |
Bute and Banamine are two of the most common non-steroidal anti-inflammatory drugs (NSAIDs) on the market, and they easily accessible to nearly every horse owner. They can be the first line of defense in emergency cases such as colic, and phenylbutazone (Bute) and flunixin meglumine (Banamine) are frequently stacked (given together) by owners, trainers, and veterinarians to treat lameness.
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| Surgical Risk Factors Associated with Colic |
September/2006 |
There are always risk factors when horses undergo surgery and anesthesia. Researchers have found that these risks are greater in horses than any other animal species. Studies have also shown that colic surgery mortality rates are higher than that of any other surgical procedure--most likely because the horse's system is already compromised when the animal is anesthetized.
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| Altitude Affects Anesthesia |
July/2006 |
High altitudes can affect an animal's blood pressure; it's the reason athletes must acclimate themselves to high altitude conditions long before they compete in them. University of California (UC), Davis, researchers were concerned that this could pose risks to equine patients undergoing surgical procedures in the field setting that required anesthesia, which is dependant upon the blood pressure.
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| Failure of Racehorses to Train and Race |
July/2006 |
It's commonly known that racehorses endure extreme physical and mental stresses preparing for a racing career, which can lead to injuries and illnesses. In a University of Cambridge study, researchers sought to quantify ailments endured by today's racehorses.
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| Good Prognosis for Olecranon Fracture Repair |
June/2006 |
Olecranon (point of the elbow) fractures are common orthopedic problems in foals often attributable to being kicked while playing, rambunctious behavior, or falling over backward (which they are more apt to do than older horses).
In a joint study from the University of Missouri (UM) Comparative Orthopaedic Laboratory and Hagyard Equine Medical Institute in Lexington, Ky.
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| Repeated Follicle Aspiration Doesn't Affect Fertility |
June/2006 |
Veterinarians are increasingly using repeated transvaginal ultrasound-guided follicle aspiration (TVUFA) to collect eggs from mares for research and clinical applications. Currently, the main use of TVUFA for client-owned mares is for oocyte transfer, which involves collecting an egg from a subfertile mare and transferring it to a fertile recipient mare where it is fertilized.
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| Researchers Explain Short Shoeing Intervals |
May/2006 |
Farriers and veterinarians have said for years that shoeing intervals should be at most six to eight weeks, but why? Researchers from the Equine Performance Laboratory at Utrecht University (Netherlands) say it's because horses must compensate for the extra hoof growth by lowering the coffin joint angle, which places additional strain on their deep digital flexor tendons (DDFT).
Meike van Heel, MSc, BSc, PhD, and her colleagues examined the hoof growth and angle of nine sound Warmblood horses over an eight-week period.
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| Risk Factors Associated with Renal Failure |
May/2006 |
In a recent study, University of Georgia College of Veterinary Medicine researchers looked for patterns in horses referred to the hospital with renal (kidney) insufficiency in order to detect the disorder earlier. Renal insufficiency is often a result of dehydration, and it is commonly associated with horses that are colicking and/or horses with increased creatinine (a kidney enzyme) levels.
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| Varying Glucosamine Levels in Products |
April/2006 |
A Canadian study evaluating oral equine glucosamine supplements found glucosamine levels didn't always meet product label claims. Additionally, based on dosing recommendations and actual glucosamine content, the recommended maintenance dosage (10 grams of glucosamine per day) would not be achieved for the majority of products.
Scott Weese, DVM, DVSc, Dipl.
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| Drug Resistance from Daily Dewormers |
April/2006 |
Are daily dewormers contributing to the development of drug-resistant parasites? A study from the North Carolina State University (NCSU) suggests they might be. The study used fecal worm egg count reduction tests (FWECRT) to evaluate small strongyle resistance to oral Strongid paste dewormer (pyrantel pamoate 6.
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| Musculoskeletal Disease Biomarkers |
March/2006 |
Colorado State University (CSU) researchers have found significant patterns of six different signals of damage or "biomarkers" in the serum of racehorses with certain musculoskeletal diseases.
Biomarkers are indicators of abnormal skeletal tissue turnover.
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| Three Years of Racing Deaths in Australia |
March/2006 |
An Australian survey found that euthanasia for catastrophic forelimb injury was the most common Thoroughbred racehorse fatality. Also, sudden death (not as the result of euthanasia) contributed more to racing fatalities than previously thought. Analyzing point-of-death blood samples could help scientists better pinpoint the triggers of sudden deaths.
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| Forelimb Conformation of the Growing Thoroughbred |
March/2006 |
University of Wisconsin researchers found certain forelimb characteristics in growing Thoroughbreds are associated with higher birth weights, and their carpal (knee) conformation is associated with the parents'. Both genetics and environment affect forelimb conformation.
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| AAEP Convention 2005: New Treatment for Osteoarthritis |
February/2006 |
Osteoarthritis is a degenerative disease that affects joint cartilage and bones and leads to arthritis within the joint. In a recent study, researchers at the Colorado State University (CSU) Equine Orthopaedic Research Center (EORC) examined the effects of a new product called autologous conditioned serum (ACS) to stimulate the production of interleukin-1 receptor antagonist (IL-1Ra or IRAP), which blocks interleukin-1 proteins that are associated with joint inflammation and accelerate the deterioration of tissue. Previous studies have shown IL-1Ra blocks excessive production of synovial fluid in joints, which causes joint swelling or enlargement.
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| AAEP Convention 2005: Inflammation and Pregnancy Rates |
February/2006 |
Before heading to a breeding shed in Central Kentucky, most farms require all mares to have a clean uterine culture to look for bacteria. According to Thomas Riddle, DVM, a founder of Rood & Riddle Equine Hospital in Kentucky, uterine cytology (a microscopic examination of uterine cell types) provides a faster and more meaningful method to evaluate the health of the uterus.
Riddle and his colleagues performed a retrospective study that examined the relationship between uterine cytology, culture results, and Day 28 conception rates in 970 Thoroughbred mares bred during the 2001 to 2004 breeding seasons.
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| Forelimb Lameness Common in Barrel Horses |
February/2006 |
A Texas A&M University (TAMU) study has found that horses used for barrel racing were more often lame in their forelimbs than horses used for other disciplines. The study examined 118 Quarter Horses and Appendix Quarter Horses brought to TAMU for lameness and performance problems.
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| Evaluating Ulcer Medications |
February/2006 |
Studies have shown that gastric squamous (the non-glandular area of the stomach) ulcers affect approximately 80-95% of racehorses, and more than half of the entire domestic horse population. A recent study from Murdoch University in Australia determined that omeprazole (a proton-pump blocker) is more effective than ranitidine (a histamine inhibitor) when treating gastic squamous ulcers in racehorses.
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| Visualizing Joints During Surgery |
November/2005 |
Arthroscopic surgery in horses is commonly performed to remove abnormal pieces of cartilage, called osteochondral (OC) fragments, from the surface of joints. Visualization through an arthroscope is typically aided by distending the joint with sterile fluid.
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| Nasal Septum Resection |
November/2005 |
If the nasal septum—the bony structure that divides the left and right halves of the nasal cavity—becomes deviated or thickened, the nasal passages become narrowed and breathing is impaired. Left untreated, it can lead to exercise intolerance and respiratory distress.
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| EMND and Glucose Metabolism |
October/2005 |
EMND, or equine lower motor neuron disease, is a degenerative disorder resulting from oxidative damage to specific spinal cord nerve cells. Early on, it causes a sudden onset of trembling, shifting weight between the hind limbs, muscle twitching, abnormally increased sweating, and more time lying down. Once EMND becomes chronic, affected horses develop weight loss, altered gaits, fatigue, and general poor performance.
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| Oral Potassium for Endurance? |
October/2005 |
Endurance riding can lead to significant losses of water and electrolytes, which can cause clinical illnesses related to increased neuromuscular excitability, including cardiac arrhythmia, muscle cramping and twitching, and gut motility changes. When plasma potassium (K+) increases--as it does with increasing exercise intensity--there is a concomitant increase in neuromuscular excitability.
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| Supplementing for Semen Quality |
September/2005 |
Cooling and freezing equine semen damages cell membranes, which results in loss of motility and general viability known as "cold shock." Most domestic species have high concentrations of polyunsaturated fatty acids (PUFAs) in the semen, but the amounts of these PUFAs, particularly DHA, an omega-3 fatty acid, and DPA, an omega-6 fatty acid, vary by species. These variations influence susceptibility of semen to cold shock.
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| Dialysis to Treat Kidney Failure |
September/2005 |
Sometimes horses in renal (kidney) failure don't respond to conventional treatment--fluids, diuretics, etc. Toxins in the blood irritate the stomach, making the horse anorexic and depressed. At that point, dialysis might be the only option.
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| Puberty in Thoroughbreds |
July/2005 |
Puberty is a transitional period for horses, from a time of reproductive immaturity to a time where sexual behavior is demonstrated and sperm is ready for release in the colt, and the filly starts to cycle. Unfortunately, very little information is available about puberty in horses, including at what age and what weight most horses reach this important life stage.
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| Acupuncture for Acute Heaves |
July/2005 |
Acupuncture has become a popular alternative therapy for chronic illness in horses, especially recurrent airway obstruction (also known as chronic obstructive pulmonary disease, or heaves). Unfortunately, there are few objective studies supporting the use of acupuncture in horses, and traditional therapies such as bronchodilators, corticosteroids, and long-term environmental management are the standard.
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| Tumors of Dental Origin |
June/2005 |
Odontomas are benign tumors that arise from dental tissue in an animal's mouth. These tumors can be quite invasive, most commonly affecting the maxilla or cheekbone. They can be surgically removed, but the procedure requires aggressive, extensive resection of bone, tissue, and sometimes teeth.
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| Dermal Melanomatosis Surgery |
June/2005 |
Tumors arising from melanin-containing cells (melanocytes) in the skin go beyond benign or malignant melanoma. In fact, there are four distinct melanocyte-derived tumor types, each classified according to clinical behavior and cellular appearance. For example, two types--dermal (skin) melanoma and dermal melanomatosis--look identical microscopically and must be distinguished by clinical appearance.
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| Athletic Taping of the Lower Limb |
May/2005 |
Athletic taping is commonly used in human sports medicine to begin a physical therapy program; it stabilizes injured soft tissues and helps prevent further injury. Years of experience in the use of athletic taping as well as scientific research supports its use in humans.
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| Dental Floating Value |
May/2005 |
Maintaining dental health is believed to be critical to optimum feed intake, digestive tract health, and body condition. In Western Canada, there are about 70,000 PMU mares that usually don't get routine dental care. Researchers from the Western College of Veterinary Medicine at the University of Saskatchewan decided to see if dental floating could improve feed digestibility, increase weight gain, and improve body condition score (BCS) in some of these mares.
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| Decreasing Abdominal Adhesions |
April/2005 |
Post-operative abdominal adhesions are a significant problem in horses, as they can lead to intestinal obstruction or strangulation. In recent years, a laparoscope is used to look into the abdomen and break down any adhesions that have formed seven to 10 days after the initial surgery. Unfortunately, in some foals, new adhesions form after second-look laparoscopy, but these are generally less common and less severe.
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| WNV in Northern Indiana |
April/2005 |
West Nile virus (WNV) was first detected in Indiana horses in 2001. In 2002, the state reported 704 cases, the fifth-largest outbreak in the United States. Michael Ward, BVSc, MSc, MPVM, PhD, from Purdue University's School of Veterinary Medicine, and colleagues investigated the 2002 outbreak of WNV in northern Indiana horses.
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| Amikacin Therapy in Newborns |
March/2005 |
Aminoglycosides, including amikacin, are known for their potent activity against bacteria that cause sepsis in newborn foals. Dosage protocols for aminoglycosides have been extensively studied in humans, and conventional dosing at eight- to 12-hour intervals is now giving way to high-dose, once-daily administration. Human studies have shown that amikacin is more effective and less toxic to the kidneys when given this way.
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| Tick-Borne Illness |
March/2005 |
Diseases transmitted by ticks are becoming more widespread. Recently, a case report was published detailing a common tick-borne illness in horses called equine granulocytic anaplasmosis (EGA), once called equine ehrlichiosis. An 11-year old Hanoverian-cross gelding had recently been imported from Canada in good health and appeared normal when ridden one morning.
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| Silent Cycling of EHV in Foals |
February/2005 |
Since 1997, a multivalent equine herpesvirus vaccine (EHV-1/EHV-4) has been available in Australia, but only in killed formulation. While this vaccine is considered safer for pregnant mares, it provides only short-term protection. Before the widespread use of this vaccine in Australia, some researchers had described the emergence of a "silent cycle" introduction, where EHV-1 circulates among unvaccinated animals in the absence of clinical disease.
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| Fractures in Thoroughbred Racehorses |
February/2005 |
Musculoskeletal injury is the most common cause of lost training days for Thoroughbred racehorses. This type of injury, particularly fractures, is also cited as a major reason horses leave the industry. But the incidence and characteristics of fractures in racing Thoroughbreds are not well understood.
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| GastroGard vs. a Generic Drug |
December/2004 |
It has been reported that more than 80% of highly trained horses will develop gastric ulcers. But only one anti-ulcer drug, GastroGard, has been found to significantly decrease the risk of developing moderate to severe gastric ulcers during training (see Research Reports, The Horse, August 2004, thehorse.
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| MRI for Confirming DDF Tendonitis |
December/2004 |
Tendonitis of the deep digital flexor tendon (DDFT) in horses is a newly recognized cause of foot pain. Radiography and even ultrasonography have failed to detect abnormalities in this tendon, especially as it travels within the hoof capsule and attaches to the pedal or coffin bone. In an effort to improve the ability of practitioners to diagnose DDFT lesions within the foot, a study was performed to determine the incidence and types of DDFT injuries in horses with a history of lameness localized to the digit.
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| Injecting Cervical Facet Joints |
December/2004 |
The ability to accurately locate and inject the cervical vertebral facet joints, the joints that lie between the transverse processes of the vertebrae, has significant advantages, including the performance of regional nerve blocks and intra-articular (within the joint) injection treatments. Unfortunately, unlike humans, horses don't have readily palpable cervical facet joints.
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| Medicinal Control of Tying-Up |
December/2004 |
Dantrolene sodium (Dantrium) is used to control exertional rhabdomyolysis (ER, also called tying-up) in horses. Diagnosis of ER is typically confirmed by a finding of increased serum creatine kinase (CK), which is often greater than 1,000 IU at its peak (normal CK levels are around 200 IU). While Dantrium has been in use for about 20 years, there is little published data regarding its efficacy in horses.
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| Minimizing Abdominal Adhesions |
October/2004 |
Small intestinal strangulation or distension colic can produce ischemia (lack of blood flow), depriving tissues of oxygen and nutrients. As blood flow is restored, known as reperfusion, newly circulating blood triggers several cellular reactions resulting in generation of oxygen radicals and inflammation that promotes fluid and cellular leakage into surrounding tissue. This "reperfusion injury" can lead to postoperative complications, including ileus (intestinal obstruction), scarring, and adhesion formation (adhering of the resected intestine to nearby tissues).
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| Warm Springwater Immersion |
October/2004 |
Immersion of the body in natural springwater has been studied extensively in humans and dogs for its healing effects. The theory behind immersion is its ability to temporarily suppress the sympathetic nervous system (SNS, the part of the nervous system responsible for the "fight or flight" response) and enhance the parasympathetic nervous system (PNS, the part of the nervous system responsible for the "rest and restore" response), inducing relaxation.
The Joban Branch of the Equine Research Institute of the Japan Racing Association in Fukushima has been using springwater immersion to treat chronic bone and tendon injuries in racehorses for more than three decades.
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| Anesthesia and the Equine Brain |
September/2004 |
In horses, the gas anesthetic isoflurane can produce decreases in mean arterial pressure (MAP) as well as cerebral perfusion pressure (that pushes blood into the brain). The implication is that decreased cerebral perfusion pressure leads to decreased cerebral blood flow and oxygenation, which could damage brain cells.
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| Arthroscopy for Meniscal Tears |
September/2004 |
A meniscus is an interarticular (between joints) synovial cartilage or membrane. Meniscal tears in the stifle joint are well described in human athletes and dogs. Despite a few published reports in horses, however, the condition remains difficult to diagnose and even more difficult to treat because of a paucity of information regarding arthroscopic findings and prognosis.
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| Efficacy of Common Anti-Ulcer Medications in Racehorses |
August/2004 |
Gastric ulcers are so common in racing horses that many equine practitioners maintain their racing patients on anti-ulcer medications to prevent and treat gastric ulcers. Reports in the literature place the percentage of racing horses in training with endoscopically visible gastric ulcers at grater than 80%.
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| Injuries Associated With Steeplechase Racing |
August/2004 |
Studies have been conducted to determine the types of injuries that occur in horses on flat racetracks in the United States and steeplechase and hunt races in the United Kingdom. Unfortunately, there is a paucity of data on injuries occurring during U.
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| Treating Navicular Disease From Inside the Bone |
July/2004 |
Healthy bone undergoes constant metabolic change to prevent bone loss or abnormal remodeling (cell turnover) that can occur with loading. Horses with navicular disease can have abnormal remodeling and formation of osteolytic lesions (areas of broken-down bone) within the navicular bone. This might be due to an imbalance in bone metabolism, with increased bone resorption.
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| Endurance and Endotoxemia |
July/2004 |
Endotoxemia in horses is usually associated with severe infections, inflammation, and colic. Endotoxin from intestinal bacteria activates release of inflammatory mediators such as thromboxane B2 (TxB2), tumor necrosis factor-alpha (TNF-alpha), prostaglandin F1-alpha (PGF1-alpha), and interleukin-6 (IL-6). These mediators produce malaise, fever, dehydration, cardiovascular collapse, organ failure, and sometimes death.
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| Trilostane for Cushing's Disease |
June/2004 |
Equine Cushing's syndrome (ECS), or hyperadrenocorticism, is caused by an excess of cortisol. This syndrome produces signs including excessive hair growth (hirsutism), lethargy, fat redistribution under the skin, chronic/relapsing laminitis, and increased drinking and urination (polydypsia/polyuria). The drug pergolide is commonly recommended as treatment for ECS.
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| Measuring Hemoglobin and Red Blood Cells in the Field |
June/2004 |
Many equine illnesses and injuries require rapid determination of blood's oxygen-carrying capacity. Hemoglobin (Hg) can be measured, and packed cell volume (PCV) can be estimated, providing a good indication of how much oxygen can circulate. However, Hg measurement requires transport of a blood sample to a laboratory.
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| Drug-Resistant Parasites |
May/2004 |
When a weanling on a North Carolina breeding farm was diagnosed with larval cyathostominosis, Dianne Little, BVSc, MRCVS, equine surgery resident and PhD candidate in the Department of Clinical Sciences in North Carolina State University's (NCSU) College of Veterinary Medicine, was suspicious of anthelmintic resistance. Parasites resistant to dewormers and associated diseases, such as larval cyathostominosis, aren't unusual in her experience.
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| Identifying Sacroiliac Joint Pain |
May/2004 |
A diagnosis of sacroiliac joint (SI) pain tends to be one of exclusion, after other causes of hind limb lameness have been ruled out. To simplify the diagnostic process, researchers in the United Kingdom conducted a study involving 74 horses suspected of having SI pain. The objective was to use both nuclear bone scan (scintigraphy) and a local anesthetic block to positively identify abnormal SI regions.
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| Ivermectin Resistance in Foals |
April/2004 |
On many breeding farms, Parascaris equorum (roundworms) and other intestinal parasites in young foals are now controlled with one class of dewormer. This has become common because of the belief that certain drugs, like ivermectin, are highly effective and free from parasite resistance. However, a recent report from Ontario, Canada, describes foals from a breeding farm with fecal egg counts for P.
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| Miniature Horses' Eyes |
April/2004 |
It is tempting for veterinarians to use laboratory reference ranges collected from full-sized horses when treating miniature horses. This is not always appropriate, however, as miniature horses have some breed characteristics that are only now becoming apparent. In fact, researchers at Michigan State University (MSU) have been diagnosing ocular abnormalities in miniature horses more frequently over the past few years.
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| A Prosthetic Eye for the Horse |
March/2004 |
When Brian Gilger, DVM, MS, Dipl. ACVO, associate professor of ophthalmology at North Carolina State University (NCSU), examined a Thoroughbred gelding referred to NCSU's College of Veterinary Medicine, he discovered thick, cloudy material throughout the anterior chamber of the right eye that obscured his view of the inner eye. Using ocular ultrasonography, he was able to diagnose complete retinal detachment with a large retinal tear.
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| Relieving Rectal Pain in Mares |
March/2004 |
Roman Skarda, DrMedVet., PhD, professor in the Anesthesia Section of the Department of Veterinary Clinical Sciences at The Ohio State University, has studied techniques of epidural and spinal analgesia in horses for 20 years. For the past seven years, he has focused on acupuncture and alternative methods of analgesia, and is currently using an experimental model to re-create rectal pain in horses.
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| Longitudinal Tears in the DDFT |
March/2004 |
Horses with chronic inflammation of the digital flexor tendon (DDFT) sheath that doesn't respond to conventional therapy might be suffering from longitudinal tears in the DDFT. Warmbloods which suffer from chronic annular ligament constriction syndrome (ALCS) also could have hidden longitudinal tears.
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| Model for Reperfusion Injury |
March/2004 |
During colic surgery, it can be difficult to judge whether twisted bowel deprived of oxygenated blood, a process called ischemia, will recover sufficiently once it is replaced and blood flows again. While the bowel might look healthy on the outside, the internal surface might have suffered great damage, causing it to malfunction once reperfusion occurs (blood flow is restored).
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| R. equi on Breeding Farms |
February/2004 |
Rhodococcus equi is an organism that lives in soil, requiring warmth and nutrients found in horse manure to grow and spread among equine populations. It is the most common cause of pneumonia in foals one to four months of age, bringing costly losses on affected breeding farms. Recently, a study was conducted at Texas A&M University in an effort to identify characteristics of breeding farms that put them at risk for outbreaks of R.
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| Aging Changes in Muscles |
February/2004 |
Electromyography (EMG) aids in differential diagnosis of neurogenic (controlled by the nervous system) versus myogenic (taking place or functioning in ordered rhythmic fashion because of the inherent properties of cardiac muscle rather than specific neural stimuli) disorders in the muscle. The technique involves systematic placement of a needle into muscle beds and examination on a monitor of resulting activity of muscle fibers and surrounding nerves, called motor unit action potentials (MUAP).
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| Linking Chronic Laminitis to Immunologic Hyperreactivity |
February/2004 |
The pathogenesis of chronic laminitis remains unclear. There is growing evidence, however, of a link between this condition and the development of certain systemic diseases, such as kidney disease, that involve small blood vessel damage. There might also be a link between routine vaccination and acute episodes of chronic laminitis.
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| Optimizing Implant Therapy in Cycling Mares |
January/2004 |
Deslorelin acetate implants (Ovuplant from Fort Dodge Animal Health) have proven highly successful at inducing ovulation in mares. Implanted mares typically ovulate within 48 hours. Unfortunately, despite administration of prostaglandin during diestrus, a percentage of mares with implants, perhaps as many as 1 in 4, experience a prolonged interval to the next ovulation.
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| Understanding Congestive Heart Failure |
January/2004 |
Congestive heart failure is a term describing a group of clinical signs that develop as a result of other cardiac diseases. As the name implies, equine congestive heart failure is generally an endpoint of disease, and it is considered rare in horses. There is little information available about congestive heart failure, but a study from North Carolina State University re-examined cases of the problem in an effort to define the most common signs, diagnostic findings, and prognosis.
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| Tell-Tale Signs of West Nile Virus |
January/2004 |
Unfortunately, clinical signs of West Nile virus (WNV) aren't unique, making it difficult for practitioners to suspect WNV above other neurologic diseases. For this reason, researchers from the University of Florida set out to closely scrutinize the clinical signs of WNV to see if any are particularly unusual.
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| Diagnosing Grass Sickness |
November/2003 |
Equine grass sickness is so named because it occurs in the spring in pastured horses which are eager to eat plentiful green grass. Its cause is unknown, but the result is destruction of the nerves of the gastrointestinal system, which is often rapidly fatal. While extremely rare in North America, grass sickness is a problem in Scotland, northern England, Switzerland, and Australia.
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| Folic Acid Supplementation |
November/2003 |
Sulphadiazine and pyrimethamine are used in combination to treat equine protozoal myeloencephalitis (EPM). These drugs interfere with folic acid (folate) metabolism, a vitamin essential for survival of the causative protozoon Sarcocystis neurona. In human patients, these drugs can cause folate deficiency.
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| Diagnosing Septic Foals |
November/2003 |
No one test can reliably diagnose septicemia (systemic infection) in a foal. The clinician must wait for the results of blood cultures, which can take days. However, preliminary studies of a blood protein called serum amyloid A (SAA) have shown it to rapidly increase in response to inflammatory diseases.
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| Shoeing for Chronic Laminitis |
October/2003 |
There are limited options for effective treatment of horses with lameness due to chronic laminitis. A common practice involves therapeutic shoeing, which is intended to reduce pain, aid in healing, and help return the horse to activity. Recently, researchers from Texas A&M University examined four types of therapeutic shoes to determine their effectiveness at rapidly reducing pain and lameness in horses with chronic laminitis.
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| Forages for Stabled Horses |
October/2003 |
Busy training schedules and fears about injury often limit pasture access for performance horses. Prolonged stall confinement, however, can be detrimental to a horse's attitude. Boredom can lead to destructive behaviors, including weaving, pawing, and ingestion of bedding.
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| Steroid Effects on the Knees |
October/2003 |
During intensive training, young racehorses experience a thickening in the layers of bone under the cartilage of joints. These layers, called subchondral (located nearer the surface) and cancellous, become harder and better able to handle the rigors of training. Unfortunately, the process is painful, especially in the carpus (knee).
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| EPM Testing in Foals |
July/2003 |
Diagnosis of equine protozoal myeloencephalitis (EPM) involves a technique called Western blotting (WB), which identifies antibodies against Sarcocystis neurona, the parasite responsible for the disease. A positive result on WB does not guarantee current infection, but rather exposure, since antibodies and not organisms are being identified.
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| Tenoscopy for Tendon Injuries |
July/2003 |
Penetrating injuries near the fetlock can be very serious because of their proximity to the deep digital flexor tendon (DDFT), which flexes the lower limb joints, and its sheath. While a horse might have only a small cut or puncture wound, the internal injury can create severe or even non-weight-bearing lameness.
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| Does Fat Really Impact Digestion of Fiber? |
July/2003 |
Dietary fats are important components of performance horses' diets because they are calorie-dense and energy-rich. Previous studies have shown, however, that diets high in soybean oil interfere with fiber digestion in trotters. It is unclear whether feeding poorly digestible carbohydrates, like cornstarch, compounds this problem by overloading the cecum and altering its bacterial population.
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| Anesthesia Options for Foals |
June/2003 |
Young foals are notoriously difficult to anesthetize because of their extreme sensitivity to most anesthetic drugs. Ideally, foals are anesthetized using only an inhaled anesthetic. One inhalant, isofluorane, has proven itself easy to use with relatively mild adverse effects.
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| Dietary Clues to Tying-Up |
June/2003 |
Recurrent exertional rhabdomyolysis (RER, a type of tying-up) is an inherited disorder in Thoroughbreds. Research suggests that RER involves an abnormality in the regulation of calcium in muscle cells. High-grain diets have been implicated as triggers of acute episodes, perhaps because of their influence on calcium balance.
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| Overtraining in Standardbreds |
June/2003 |
There is a fine line between striving to maximize a horse's performance and pushing the animal beyond his physical limits. Standardbred racehorses experience a decrease in body weight and an abnormal decrease in blood cortisol when they are overtrained. Researchers from New Zealand recently conducted a study to see if there are any other physiologic changes associated with overtraining.
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| Glucosamine Supplement Efficacy |
May/2003 |
Glucosamine is a popular nutritional supplement that horses are fed in hopes of protecting them from osteoarthritis. Researchers studying the mechanisms of osteoarthritis have identified several compounds, called markers, that are unique to the cartilaginous joints. Increased concentrations of these markers in the blood signify damage to cartilage and/or bone.
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| Challenges of Assessing Pain |
May/2003 |
Because of its subjective and complex nature, the severity of a horse's pain is very difficult to assess. Recently, a comprehensive review was published by the University of Minnesota outlining the definitions of the types of pain and the difficulties associated with its assessment in animals.
Pain is broadly classified as acute (of short duration) or chronic (persisting over time), then further classified as superficial or deep within the body, and somatic (bone, muscle, ligament pain, etc.
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| Evaluating Spinal Cord Disease |
May/2003 |
Spinal cord disease in horses is fairly common, but it can be difficult to precisely diagnose. Ancillary tests such as cerebrospinal fluid analysis, contrast myelography, and electromyelography can be helpful, but also somewhat risky. There is another diagnostic technique used in humans that is not painful and has no serious side effects.
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| Flea Control Product for Fungal Endometritis in Mares |
April/2003 |
Lufenuron is a once-a-month flea control product for dogs and cats. The active ingredient inhibits chitin production; chitin is a component of the outer surface of many insects. Fungal organisms also contain chitin in their cell walls, making them susceptible to lufenuron.
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| Conservative Therapy for Crooked Foals |
April/2003 |
The most common angular limb deformity in foals is carpus valgus (sometimes called toeing out) in which affected foals have limbs that flare outward below the carpus (knee). This deformity can be corrected surgically with hemi-circumferential periosteal transection and elevation (HCPTE).
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| Intravenous Nutrition for Colicky Horses |
April/2003 |
Horses which survive an episode of severe colic can be temporarily unable to eat. Anorexia, nasal regurgitation, and ileus (lack of bowel movement) prevent oral feeding. After several days of malnutrition, the horse's ability to heal is impaired.
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| Blood Test for Ovarian Tumors |
March/2003 |
Granulosa-theca cell tumors (GTCTs) are usually tentatively diagnosed by rectal palpation and ultrasound examination after an owner complains of poor performance or aggressive, sexual, stallion-like behaviors. However, the diagnosis can't be confirmed unless an exploratory laparotomy is performed and the tumor is biopsied (or removed and sectioned for histopathology).
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| Lasers for Removing Skin Masses |
March/2003 |
Skin masses in horses have historically been removed by surgical excision (cutting them out). Regardless of the type of mass, the surgeon's goal is to remove all of the tissue, limit hemorrhage, and prevent infection while achieving the best possible cosmetic outcome. Equine surgeons at Purdue University have been using a carbon dioxide (CO2) laser in place of a scalpel blade to remove certain masses in an attempt to minimize complications and improve cosmetic outcome.
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| Treating Shoulder Lameness |
March/2003 |
There is an uncommon type of shoulder lameness in horses that produces a dropped elbow and flexing of the carpus (knee) and pastern at rest. At work, affected horses are typically severely lame with a significantly decreased forward phase of the stride. Radiographs of the shoulder in these cases usually reveal a combination of biceps tendonitis, bursitis, and inflammation of the bone (osteitis) in the area of attachment of the biceps tendon.
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| Predicting Muscle Problems |
December/2002 |
Competitive endurance riders know that horses lose fluids and electrolytes during strenuous rides. Calcium and magnesium are also lost during prolonged aerobic exercise. Low blood calcium (hypocalcemia) allows sodium to enter nerve cells, leading to hyperirritability of nerves, muscle twitching, cramping, and even paralysis.
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| Antimicrobials in Colic Surgery |
December/2002 |
Colic surgery in horses is classified as a "clean contaminated" procedure because incisions into the intestine can allow bacteria to contaminate the sterile abdomen. Thus, prophylactic (preventive) antibiotic therapy is often administered prior to surgery in case the intestine must be entered.
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| Exercise and Bone Development |
December/2002 |
Beneath the smooth surface of articular cartilage, subchondral bone gives structural support to joints. Normally, newborn foals have a lot of water in this layer, which is slowly replaced by calcium and collagen as the foal weights his joints. Research has shown that abnormalities in subchondral bone precede abnormalities in articular cartilage.
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| Joint Disease Model |
November/2002 |
Horse owners are familiar with the devastating effects of osteoarthritis (OA) in performance horses. Methods to detect OA earlier, treat it more effectively, and slow its course are heavily researched. One problem, however, is the lack of an accepted laboratory model for equine OA.
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| Chronic Uterine Torsion in Mares |
November/2002 |
In late pregnancy, mares are susceptible to a dangerous complication called uterine torsion. Accounting for 5-10% of obstetrical emergencies, twisting of the uterus can be fatal to fetus and mare if left untreated. The hallmark of acute uterine torsion is colic, and diagnosis is based on rectal palpation and ultrasound examination.
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| Foal Sex Selection |
November/2002 |
Sex selection of foals prior to conception is highly desirable for horse breeders. Currently, sperm can be sorted by their X and Y chromosomes, improving odds of sex selection through artificial insemination. Flow cytometry measures DNA in cells and can sort sperm, but it's time-consuming and damages sperm, leading to great losses during the procedure.
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| Cardiovascular Changes With Moldy Corn Poisoning |
October/2002 |
Fumonisins are toxic byproducts of the fungus Fusarium verticilloides, which often grows on corn. These mycotoxins can cause leukoencephalomalacia (moldy corn poisoning) in horses, and are undetectable to the naked eye. Horses exposed to only 0.
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| Clostridium in Mares and Foals |
October/2002 |
Newborn foals are especially susceptible to gastrointestinal diseases such as clostridial enterocolitis, which is characterized by abdominal pain, diarrhea, toxemia, shock, or death without prior signs. While this disease occurs only sporadically, it is highly fatal.
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| Polysaccharide Storage Myopathy and Back Pain |
August/2002 |
As many as 40% of all cases of equine back pain are the result of soft tissue injury. The primary causes include chronic and recurrent exertional rhabdomyolysis (CER and RER, respectively), and an inherited enzyme deficiency called polysaccharide storage myopathy (PSSM). Quarter Horses, Warmbloods, and draft horses are particularly susceptible to PSSM, which prevents normal metabolism of glycogen, a stored form of carbohydrate found in muscle.
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| Preventing Airway Obstruction |
August/2002 |
During periods of intense exercise, portions of the upper airway can collapse, interfering with breathing. The cause of these obstructive episodes, most notably dorsal displacement of the soft palate (DDSP), is yet unknown. In other species, receptors in the upper airway stimulate surrounding muscles to contract, dilating and stabilizing the airway during exercise and preventing collapse.
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| Fatigue in Racehorses |
July/2002 |
While visibly obvious, fatigue is hard to quantify. Electromyography (EMG) measures conduction along nerves in a particular muscle group--as muscle fibers fatigue, EMG signals shift from high to low. Taking EMG readings during galloping is unreliable, however, because signals are susceptible to inaccuracies from lead changes.
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| Screening for Joint Disease |
July/2002 |
Veterinarians are quite capable of identifying a painful joint in a lame horse, but determining what is occurring within the joint and how far it has progressed is not yet possible without removing synovial fluid or exploring the joint with arthroscopic surgery. Even with synovial fluid samples, the duration of disease and extent of cartilage damage is often unclear.
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| Laryngeal Paralysis |
June/2002 |
Partial paralysis of the larynx prevents maximal opening of the equine trachea. Affected horses can move air, but breathing noises occur, especially during exercise. The most common form of laryngeal paralysis is recurrent laryngeal neuropathy (RLN), which involves degeneration of the recurrent laryngeal nerve.
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| Joint Fusion to Eliminate Lameness |
June/2002 |
Joint arthrodesis is a procedure that locks a joint by fusing bones together. The procedure is used in the pastern joint of horses to treat lameness due to severe osteoarthritis, fractures, bone cysts, and various limb deformities in foals. Surgical arthrodesis is performed by removing articular cartilage and placing screws across a joint to stabilize the area until new bone grows.
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| Modifying Semen Extender |
June/2002 |
Stallion semen is particularly susceptible to freeze-thaw damage, so multi-step procedures are being developed and evaluated to slowly extend and cool the semen prior to freezing it. In addition, the common semen extender INRA82, developed at INRA-Haras Nationaux in Nouzilly, France, is being modified with various additives in an attempt to improve it.
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| Acupuncture and Microdose Prostaglandin in the Mare |
May/2002 |
Prostaglandin F2 alpha (PG) is used to shorten a mare's cycle and hasten ovulation for breeding. Unfortunately, the standard PG dose (5 mg) also causes undesirable side effects, including sweating, trembling, increased heart rate, and even signs of colic. There is growing interest in devising a method to use less PG and reduce side effects.
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| Feeding Practices and Colic |
May/2002 |
There are multiple causes of colic, some of which are related to diet, stabling conditions, and activity level. Colic is painful for the horse, expensive to treat (especially if it requires surgery), and hard to predict. Determining which contributing factors for colic are most problematic would greatly assist in its prevention.
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| Jump Landings and Tendon Strain |
May/2002 |
Lameness in show jumpers is often caused by forelimb tendon injury. The superficial digital flexor tendon (SDFT) is most frequently injured, followed by the interosseus tendon (IT), and the accessory ligament (AL), while the deep digital flexor tendon (DDFT) is rarely injured. Repetitive landings over high fences produce significant forces on these tendons.
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| Small Intestinal Colic Surgery and Predicting Survival |
April/2002 |
While surgical correction of colic in horses has been performed at referral hospitals for many years, it has been difficult for horse owners to get reliable information about survival rate. The prospect of extremely expensive colic surgery coupled with weeks and even months of recovery time must be weighed against some idea of whether the horse will survive.
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| Risk of Equine Viral Arteritis from Imported Stallions |
April/2002 |
Equine arteritis virus (EAV) causes a flu-like illness in adult horses called equine viral arteritis, and is responsible for abortion in mares and pneumonia in foals. Stallions can be become persistently infected and shed the virus in their semen.
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| Predicting the Effects of Farriery Using a Computerized Model |
April/2002 |
A talented farrier and knowledgeable veterinarian can often do wonders for a lame horse. Applying corrective shoes can change the forces acting on the feet, improving many foot problems. Unfortunately, even the most talented farrier can overcorrect a horse's foot, perhaps making the lameness worse.
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| Phlebotomy for Thickened Blood |
March/2002 |
Some Standardbred trotters develop a condition called red cell hypervolemia (RCHV), a thickening of the blood due to an increase in the number of red blood cells. This increase in red blood cells is a result of intense exercise programs, and is considered a common finding, at least in trotters racing in Sweden.
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| Stallion Behavior Immunization |
March/2002 |
Gonadotropin-releasing hormone or GnRH can be thought of as the master reproductive hormone. In stallions, GnRH is responsible for initiating a hormonal cascade that stimulates production of testosterone and other hormones necessary for breeding behavior and normal sperm production. However, there are times when sexual behavior and aggression are detrimental, particularly in the show ring.
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| Limitations of Diagnostic Ultrasound of Bowed Tendons |
March/2002 |
Diagnostic ultrasound has become a popular means of monitoring the healing of superficial digital flexor tendon (SDFT) injuries, also known as bowed tendons. As image analysis software has been developed, the technique has become more widespread.
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| Monitoring Sand Colic With Radiographs |
February/2002 |
Ingestion of sand is an unfortunate consequence of vigorous grazing on sandy soil. The equine digestive tract can handle a certain amount of sand without difficulty, but too much sand can lead to impaction and colic. Medical treatments, including psyllium powder, magnesium sulfate, and mineral oil, can be effective at clearing sand, but might require several weeks to work.
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| Intradermal Skin Testing May Not Be Reliable for Diagnosing Heaves |
February/2002 |
Allergens in the pasture and barn are believed to trigger chronic obstructive pulmonary disease (COPD or heaves) in horses. It is unclear whether simply developing an allergy leads to COPD, or if a horse must be born susceptible to the disease. In an attempt to answer this question, researchers at The Ohio State University recently gathered 38 horses, some with and some without COPD, and tested them for allergies using standard intradermal skin testing with 73 common allergens.
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| The Role of Bovine Papillomavirus in Equine Sarcoids |
February/2002 |
Bovine papillomavirus (BPV) has long been suspected of playing a role in the development of sarcoid tumors in horses. Different subtypes of the virus, BPV-1 and BPV-2, have been identified in individual sarcoid biopsies. It is not clear, however, whether BPV is present in all sarcoids.
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| Dewormer Resistance in Small Strongyles |
January/2002 |
Small strongyles are some of the most problematic internal parasites in horses. Infected horses can experience a wide range of symptoms, from rough hair coat, poor growth, and suboptimal performance to life-threatening chronic diarrhea, colic, and severe weight loss. The most effective means of controlling small strongyles is the regular use of deworming medications.
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| Navicular Disease: Genetic or Acquired? |
January/2002 |
Navicular disease can derail a performance horse's career. Arthritis-like changes in the navicular bone, including cysts, channels, chip fragments, and bony spurs, become visible on radiographs, but there is controversy about the connection between such changes and clinical lameness. Does intense work physically alter the shape of the navicular bone over time? Or is shape determined genetically, leading to lameness regardless of a horse's level of performance? A group of researchers in the Netherlands recently set out to determine how shape and condition of the navicular bone relate to clinical signs of navicular disease.
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| Diagnosing West Nile Virus |
January/2002 |
A recent report outlined a series of cases of West Nile virus infection in horses seen at the University of Pennsylvania's New Bolton Center. The findings might help horse owners and veterinarians identify this infection more readily.
Eight horses from New York and New Jersey were referred to New Bolton Center with evidence of neurological disease.
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