Equine Medicine

Add these five plants to your veterinary watch list for flora that could be deadly to horses.

Switzerland -- A new list of equine prohibited substances was approved by the Fédération Equestre Internationale (FEI) and prohibits the use of non-steroidal anti-inflammatory drugs (NSAIDs) in competition.

New clinical guidelines have been developed for the care of racehorses by the AAEP.

In a recent study, Iowa State University researchers delved into the art of administering supplemental oxygen to neonatal foals.

Small colon impaction is a relatively infrequent cause of colic. However, when it does occur, it can be difficult to recognize and to manage. We have noticed over the last several years that many of these cases are initiated by diarrheal disease, making the eventual diagnosis of an obstructive condition unexpected by the veterinarian.

The use of underwater treadmill exercise for training and rehabilitation of horses has become increasingly popular in recent years. Many claims are made as to the usefulness of this form of exercise in horses; although relatively little published information is available to substantiate these assertions. In humans, underwater treadmill therapy has long been recognized for benefits in rehabilitation.

Characterized by clinical and laboratory findings of muscle damage not associated with exercise. Includes inflammatory, nutritional, toxic, traumatic, metabolic, congenital, immune mediated and idiopathic causes of muscle disease.

There are other agents in each of the above categories, but these drugs can be used as examples in order to develop a treatment plan. For a horse that is actively showing signs of colic, an abbreviated physical examination (heart rate, mucous membrane color, and capillary refill time) should be performed before administering an analgesic.

There are two major reasons horses with colic may require fluid therapy: hypovolemia and endotoxemia (or sepsis). Hypovolemia results from decreased intake, loss of fluid (typically sweat or reflux), and sequestration of fluid (typically in horses that have intestinal obstruction).

The epidemiology of R. equi remains ill-defined and continues to evolve. Two epidemiologic questions of clinical importance regarding Rhodococcus equi foal pneumonia are "Why are some foals affected while others in the same environment remain unaffected?", and "Why does the disease occur recurrently at some farms but not at others?". To answer these questions, studies performed at the level of the foal and farm, respectively, are needed.

Evaluation of the muscular system includes inspection for symmetry of muscle mass while standing square. Prior to palpation evidence of fine tremors or fasciculations should be noted. Palpate entire muscle mass for heat, pain, swelling or atrophy comparing contra lateral muscle groups.

The emergence of methicillin-resistant Staphylococcus aureus (MRSA) as a major human health concern has heightened awareness of the occurrence of this agent in companion animals, including horses. The purpose of this presentation is to review what basic knowledge equine practitioners should have regarding MRSA and other methicillin-resistant staphylococcal species in horses.

Muscle atrophy refers to a decrease in muscle size, particularly in muscle fiber diameter. Atrophy can reflect a disorder of the muscle cells (myogenic atrophy) or loss of neural stimulation to the muscle cells (neurogenic atrophy). Trauma, infection and nervous disorders are all causes of atrophy in horses.

The major concern of any fracture repair is to maintain adequate stability for fracture healing to occur. The stability provided by open reduction and internal fixation (ORIF) is difficult to achieve with other methods of fracture repair. However, ORIF invades the fracture site, can lead to further disruption of vasculature and soft tissue and may provide a mechanism for infection to develop or persist.

Foals are often afflicted with limb deformities, and they are classified as flexural or angular deformities. Occasionally, rotational deformities are also present. Many of the congenital angular limb deformities correct with no treatment or with only conservative treatment.

The principles of evidence-based medicine (EBM) were first developed by clinical epidemiologists during the late 1980s. EBM has been described as "the integration of the best research evidence with our clinical expertise and our patient's unique values and circumstances".

The gold-standard for diagnosis of Rhodococcus equi pneumonia is isolation of the organism from fluid obtained by tracheobronchial aspiration (TBA) from a foal with clinical signs of pneumonia, preferably accompanied by cytologic evidence of sepsis, sonographic or radiographic evidence of pneumonia, or both.

Equine practitioners frequently deal with septic wounds, arthritis, osteomyelitis and tenosynovitis. The primary mechanisms of treatment should always include physical debridement and lavage. Most treatment regiment include systemic antimicrobials and antiinflammatories. A limiting factor in some cases is the ability to obtain effective concentrations of antimicrobials to the sites of infection or contamination.

Simple obstruction: an obstruction of the intestinal lumen without compromise to the blood supply. However, fluid is continually secreted into the small intestine and is not absorbed. As the intraluminal pressure increases intestinal mucosal capillaries are compressed.

Strangulation obstruction of the small intestine is frequently fatal because of simultaneous occlusion of the intestinal lumen and its blood supply, resulting in progressive necrosis of the mucosa, and development of endotoxemia. Among the more common causes of this condition are strangulating lipomas and entrapment within a natural internal opening or a mesenteric defect.

Critical appraisal of reports entails 3 fundamental steps: 1) determining if study results are valid; 2) assessing the clinical importance of study findings; and, 3) assessing if the results of valid, clinically important studies are relevant to our patients. A foundation for applying these 3 steps is a hierarchy of study types for EBM, which places a premium on those that are patient-based. Clinical importance has many interpretations, but in terms of quantification it is best assessed in reference to the magnitude of the observed association(s) in a study.

Early studies of shock waves (SWs) for ureteral stones resulted in radiographically evident remodeling of the pelvis.1 These findings sparked the initial studies investigating the use of SWs in orthopedic applications.

Generally, horse owners are astute at detecting signs of colic. These may include subtle not being enthusiastic about coming up from the field in the morning, not showing interest in other horses and people, or not finishing their feed. These signs should be taken seriously because in a number of occasions, these are the first signs of colic.

Anatomic and physiologic considerations are the basis for proper diagnostic techniques. We will discuss basic diagnostic procedures and relative pharmacological consideration to enhance the ophthalmic examination.

Among equids, R. equi infections occur almost exclusively among foaIs; infected adult horses generally have an underlying immunodeficiency, and human cases of R. equi are most commonly reported among persons infected with HIV or with other forms of immunosuppression such as that induced by drugs in transplant recipients and those receiving chemotherapy.

Equine ocular examination is very similar to small animal examination, with special considerations for the size and use of the animal being examined.

Exertional rhabdomyolysis is muscle necrosis precipitated by exercise or exertion, resulting in myoglobinuria, elevated serum CK (usually > 5,000 in acute cases) and/or elevated AST in animals with normal liver function.

There has been much published on gastric ulceration in horses in the last 10 years. In this hour we will discuss the diagnostics, risk factors and treatment of gastric ulcers. We will concentrate on current, clinically applicable information.

In horses with primary cecal impactions, there is a gradual onset of abdominal pain similar to the development of a large colon impaction. The typical time course is 5-7-days. During this time, veterinarians may use treatments for impactions, such as intravenous administration of analgesics and nasogastric administration of laxatives such as mineral oil, dioctyl sodium sulfocuccinae (DSS) or magnesium sulphate (Epsom salts).

Although there has been a substantial increase in our understanding of postoperative complications in recent years, the treatments remain very much the same. For ileus, these treatments include decompression of the stomach, replacement of fluid and electrolyte losses with parenteral fluids, and use of a variety of prokinetic agents. For adhesions, treatments include anti-inflammatory medications and antibiotics, although some of the newer physical agents such as carboxymethylcellulose offer new modalities for combating this problem.