Internal Medicine

Common gastrointestinal conditions include weight loss, diarrhoea, and chronic or recurrent colic. After a thorough clinical examination, diagnostic techniques that can be performed at Troytown Equine Centre for investigation of these cases will be selected, and may include blood tests, faecal analysis, oral/dental examination, rectal examination, abdominal ultrasonography, gastroscopy, abdominal radiography, peritoneal fluid analysis, rectal biopsies, and glucose absorption tests. Where appropriate, laparoscopic (keyhole) surgery can be performed to explore the abdomen, or in some cases full exploratory surgery may be required.

Gastroscopy is used primarily for the identification of gastric ulcers. At TEC all cases are examined using a 3.5 metre videoscope. The horse’s stomach is divided into squamous and glandular portions. Ulcers are most commonly identified in the squamous mucosa, but they can also be seen in the glandular portion of the stomach. The duodenum is the first part of the intestine after the stomach, and is also examined routinely, where ulcers and other problems are less commonly found. Troytown does monthly gastroscopy clinics where we offer the service and treatments at discounted rates.

Respiratory diseases are very common in the horse and can lead to severe, debilitating disease or poor performance, with Equine Asthma, exercise induced pulmonary haemorrhage and infectious conditions most commonly diagnosed. Investigation of these conditions would include blood analysis, videoendoscopy, ultrasonography, radiography and with sampling of fluid from the respiratory tract (including guttural pouch lavage, tracheal aspiration, bronchoalveolar lavage).

Poor performance cases are often affected by medical conditions (including some muscle diseases) which fall into the field of internal medicine; investigation of poor performance cases can often involve a collaborative approach by medical specialists and orthopaedic / lameness specialists.

Injuries or abnormalities of the eyes should always be treated as urgently as soon as signs are noticed. Some conditions can be treated with a short course of topical medication (eye drops or ointment), however, others require further investigation or more intensive treatment than can be administered at home, sometimes as frequently as every hour. Investigations could include direct examination, specialised staining, measurement of ocular pressures, ultrasound and cytological analysis of corneal scrapings.

Heart abnormalities are relatively common in the horse and can range from being insignificant to life-threatening. Heart disease may result in heart murmurs, dysrhythmias or exercise intolerance. Suspected heart problems can be evaluated with a combination of auscultation, echocardiography and colour-flow Doppler ultrasound examination. Electrocardiographs (ECGs) can be obtained at rest over a 24 hour period and during exercise using a portable recorder.

Muscular disorders can cause a variety of symptoms, ranging from tying up, focal or generalised muscle atrophy (wastage), altered gaits, or more vague signs of poor performance. For generalised muscular disorders, blood tests pre- and post exercise are routinely performed, and definitive diagnosis most reliably obtained by histopathological examination of a muscle biopsy.

When a horse is suffering from a neurological disease or injury, careful clinical examination and neuroanatomic localisation is critical. Diagnostic techniques that may then be required include blood tests, radiography or scintigraphy of the spine and sampling of cerebrospinal fluid. Radiography following injection of a dye into the spinal canal, called myelography, is performed under general anaesthesia to look for lesions that cause compression of the spinal cord.

Skin problems in horses are common and can be difficult to diagnose. Our hospital offers routine appointments and accepts referrals for all types of dermatological conditions, including allergies/immune mediated conditions; bacterial, fungal, parasitic, protozoal or viral diseases; chemical and toxic dermatoses or endocrine disorders.

Liver disease often present insidiously with non-specific signs but can be very debilitating. Initial diagnosis of liver problems is usually based on the results of blood sampling and liver function tests. However, more specific diagnosis of the type of liver pathology requires ultrasonographic examination of the liver and liver biopsy.

Endocrine diseases are very important in the horse, commonly predisposing them to laminitis which can be life threatening. Investigation of horses and ponies prone to laminitis includes testing for underlying hormonal disorders such as Cushing’s disease or insulin dysregulation. Assessment and monitoring of body condition score and bodyweight, in conjunction with dietary management, are critical. At NEH our orthopaedic consultants also work closely with farrier Will O’Shaughnessy AWCF to deliver a holistic approach to the laminitic patient.

Horses will shake their heads for a range of reasons, but vets recognise that some of the time the headshaking signs are associated with diseases and nerve problems in their heads, causing discomfort and resulting in characteristic pattern of headshaking signs.

Headshaking horses show a pattern of signs that can include some or all of the following:

• Vertical (up and down), horizontal (side to side) or rotationary (round and round) flicking of the head
• Nostril twitching or grimacing
• Nose twitching and lip smacking
• Scrubbing the nose on the floor, against their legs, on the rider’s feet, or stable walls
• Snorting (obviously all horses can snort, but where this is exaggerated it could be signs of headshaking)
• Sometimes it appears very dramatically and the horse behaves as if an insect has flown into the ear or up their nose

These headshaking signs are sometimes caused by infections, cysts, growths, and inflammation in the head that damage the trigeminal nerve that is responsible for communicating facial sensation to the brain.  More often though, the signs are related to a problem with the function of the nerve itself and we call these cases “trigeminal-mediated headshakers”.

Horses usually develop the condition between the ages of 5 and 12 years.  It can start rapidly and severely, or it can begin with very mild signs and gradually get worse over months and years. Some horses only show signs during the spring and summer, and others have signs that persist all year.