Category: EQUINE

Iris cysts are a common finding in the equine eye. More often than not, they do not cause any issues and are an incidental finding. Some; however, can grow to a size where they begin to affect a horse’s vision. Such horses generally present to us due to spooky behaviour. This is most apparent in sunny conditions, when the horse’s pupil is small and the cyst blocks light rays from reaching the back of the eye.

Treatment options

We will recommend treating iris cysts if we feel they are clinically significant – the horse in question is showing visual deficits or has started to spook.

Traditionally the treatment for iris cysts was laser ablation. We recently undertook a new technique to drain an iris cyst called ‘standing trans-corneal aspiration.’ This technique, which can be performed in suitable candidates, is performed under standing sedation, and local anaesthesia of the eye. A very thin needle is inserted into the eye, and the fluid from inside the cyst drained. The patient requires minimal medication following the procedure and most tolerate it really well.

If you would like to know more about iris cysts, please get in touch to discuss it with one of our equine vets.

Breeding season is in full swing and the team have been busy seeing lots of beautiful mares and foals.

When it comes to the actual birth, the biggest difference between horses and other species, such as cattle, is the speed of foaling. Once stage 2 (active labour) has commenced, the foal should be born within 15-45 minutes. Foals ‘dive’ out of the mare with two front feet followed by the muzzle. You should call your vet within 10 minutes of active contractions beginning if the foaling isn’t progressing, or any issues are noted. There are a variety of options available to deliver the foal, from manually repositioning to a surgical caesarean section (which fortunately is incredibly uncommon).

Staging of foaling

Stage 1 – 1-4hrs – The mare is preparing for foaling, and starts to become restless, pawing, pacing and getting up and down. She may sweat up and frequently urinate and defecate.
Stage 2 – 15-45 minutes – This is active labour, when the mare’s waters break, contractions begin and the foal is delivered.
Stage 3 – 2-4 hrs following birth – Passing of the placenta

Two complications we see during foalings are red bag deliveries and retained foetal membranes (retained placenta). These are two conditions at the opposite ends of the spectrum involving the release of the placenta.

Red bag delivery

In a red bag delivery mares will deliver the foal within the placenta, rather than it bursting to release the foal. A red velvety bag is seen first, before the foal or any fluids. THIS IS AN EMERGENCY SITUATION as once the placenta has separated from the mare, the foal will not be receiving any oxygen. The foal requires immediate delivery. The ‘red’ bag needs to be broken open using your fingers or scissors. If both the foal’s feet and nostrils are present we recommend pulling to help the foal out quickly to give it the best chance of survival.

Retained placenta

A placenta is classed as ‘retained’ when it is still attached to the uterus (womb) 3–4 hours post-partum. At this point, veterinary advice should be sought as horses are very sensitive to toxins released from bacteria on a retained placenta. These toxins can then cause endotoxemia, colic and laminitis. As vets we usually give these mares a combination of antibiotics and anti-inflammatories, to reduce the risk of endotoxemia. We also administer drugs to stimulate the uterus to contract, flush the uterus, and finally apply gentle traction on the placenta. In some circumstances it can take several visits, and over 24 hours before the placenta has loosened sufficiently to be removed. The mare may require antibiotics and uterine flushing for several days thereafter.

Foal targets

• 1 hour – Standing
• 2 hours – Nursing
• 3 hours – Passed meconium (first droppings)
• 24 hours – Antibody (IgG) blood sample

Once the foal has been born, we expect them to stand and nurse within a couple of hours. This is particularly important as foals are born without antibodies which protect them from diseases in the environment. The mare’s colostrum contains antibodies, but the foal quickly loses the ability to absorb them. Maximum absorption occurs during the first 12 hours of life, with the foal’s gastrointestinal tract gradually losing the ability to absorb antibodies such that by 24 hours absorption has ceased.

We can check the foal has received sufficient antibodies with a blood test taken at the mare and foal’s 24-hour post-partum check. If the antibody levels are insufficient, we can administer hyperimmune plasma to boost the antibody levels to a protective level. This will protect the foal from life threatening conditions such as sepsis.

Planning on breeding your mare this year? Call us on 01772 861300 to request a FREE copy of our Mare & Foal Guide or to discuss the options available with one of our experienced vets.

As the weather improves and pollen levels, as well as insect numbers increase, allergic skin disease is seen more frequently. Horses with allergic skin disease can present with itchiness or hives or both itchiness and hives together.

Sometimes it is easy to identify the trigger but more often than not, the cause is not easy to identify, and management of these horses can be incredibly frustrating with flare-ups common.

Management amendments can be made and the response to these changes monitored but in recurrent cases that we are struggling to control, skin tests (IDAT- intra-dermal allergen testing) can be performed to identify allergens which may be contributing to allergic skin disease. Skin testing remains the ‘gold standard’ diagnostic test for horses with allergic skin disease at this time.

Intra-dermal allergen testing

We are fortunate to be able to offer this service to our patients at Oakhill. Small blebs of common allergens are injected intra-dermally and the response to the allergens is checked 30 minutes, 4 hours and 24 hours following injection.

We subsequently provide our clients with a full written report detailing changes in management which may assist in managing these patients based on the results of the individual patient’s skin tests. De-sensitising vaccinations can also be formulated based on results of the skin tests to further assist in the management of these cases.

If you have any questions regarding allergic skin disease or the diagnosis and management of, please do not hesitate to contact the team.

Isabel presented to Stuart after her owners noticed that she had separated from her field mates. Once brought into the stable she was quidding and unable to eat haylage.

On examination, a significant swelling of Isabel’s right lower jaw was noted. As we were suspicious of a dental issue, after antibiotics and anti-inflammatories were administered to control her temperature and provide some comfort, radiographs (X-rays) were taken. This revealed a tooth root infection of the 3rd cheek tooth on her right lower jaw. The infection had caused lots of bony reaction with thinning and loss of parts of the jaw – the red arrow on the radiograph points towards this.

Once Isabel was stabilised and at the clinic, we proceeded with extracting the infected tooth under standing sedation and local anaesthesia (a nerve block). The tooth came out in one piece and as you can see, it was a whopper!!

Tooth root infections commonly occur in youngsters just several months after tooth eruption. Although Isabel now has one less tooth in her mouth, she is pain free and was very quickly back to eating happily as you can see.

Does your horse cough at the beginning of an exercise session? Do you often find accumulations of mucus outside your horse’s stable door? These subtle signs can indicate lung inflammation.

Formerly known as COPD or RAO, Equine Asthma is commonly seen in equine practice. For the purpose of simplicity, two forms are recognised- Summer asthma and the more traditional dust-induced form.

Both forms of the disease occur when a susceptible horse inhales either an allergen, to which they are allergic, or dust into their airway. This results in the airway spasming and the production of increased amounts of both inflammatory cells and mucus within the airway.

Affected horses present with clinical signs of varying degrees of severity. Some horses present with the subtle signs mentioned above or with a history of poor performance, whereas others present in respiratory distress and struggling to breathe.

On examination affected horses will generally have an increased breathing rate and effort combined with nostril flare. Mucoid nasal discharge may also be present. More severely affected horses may cough, have abdominal effort to their breathing and may have a ‘heave-line.’ A horse’s history combined with clinical examination findings will point towards a diagnosis of asthma but for definitive confirmation, airway endoscopy, to visualise the airway and grade airway mucus combined with laboratory analysis of respiratory tract samples is required. This will also rule in/out secondary bacterial infection.

Treatment of asthma should be based on environmental modifications plus drug therapy on an as needed basis. Horses affected by dust-induced asthma should be turned out in so far as possible. The stable environment should be closely examined. Ideally, the stable will have an inlet and outlet for airflow. Forage should not be stored adjacent to the stable to minimise the dust to which the patient is exposed. Horses should be groomed outside of the stable and fresh bedding laid when your horse is not in the stable environment. If your horse’s stable is unsuitable, try find an alternate stable on your yard that has better airflow. If feeding hay or ‘dry’ haylage, steaming is optimal to reduce dust particles but if not available, soaking should be considered. Managing Summer asthma is more challenging, but the measures outlined above should be followed to ensure stable ‘air hygiene’ is a good as possible.

Drug therapy, when needed, is based on relieving airway spasm (bronchodilators) and reducing airway inflammation and mucus production (steroids and mucolytics). Drug therapy can be provided by the oral or inhalatory routes. Oral medication includes bronchodilators, steroids and mucolytics (which serve to break-up airway mucus). From an inhalatory medication perspective, three options are available- the Equihaler, MDIs and nebulisation. The Equihaler is a licensed, steroid based product which utilises a fine mist to deliver steroid directly to the lungs. The product is very safe as the steroid acts at the lung surface only. We have had some great success using this product in cases of severe asthma and in those that did not respond to other forms of medication. MDIs, human asthma inhalers administered via a baby asthma face mask, have been utilised in equine practice for many years. These are probably most useful in relatively mild cases. Drug delivery via a nebuliser is the third inhalatory option but arguably used less frequently these days.

If you have any questions regarding asthma or think your horse may be affected, please do not hesitate to contact the team for guidance.

Our standing MRI scanner can be used to assess injuries from the hoof, up to and including the hock and carpus (knee). The scanner is specifically designed to image the lower limb in the standing horse, as this is the most common site of lameness.  It has revolutionized our understanding of the structures of the hoof, and we can now differentiate between the multiple conditions that were encompassed as ‘navicular syndrome’.

Previously, a horse with forelimb lameness that was localized to the foot, was diagnosed with ‘navicular syndrome’.  However, a lot of the time, the severity of the lameness did not fit with the mild observations noted on radiographs (X-rays). We now know, through the use of MRI, that there are many other anatomical structures that could be injured and causing the lameness. With forelimb lameness being a common problem in horses, this diagnostic imaging tool means we can target rehabilitation, farriery, and treatment more specifically.

Injuries identifiable on MRI would include deep digital flexor tendon lesions within the hoof. Without the use of MRI this condition would have been misdiagnosed, leading to inaccurate management and unsoundness. MRI can also assess ligaments within the hoof capsule, such as the collateral ligaments of the coffin joint, which are often painful when horses are lunged in a circle. This amazing imaging modality also shows us the degree of inflammation within synovial structures such as the coffin joint and navicular bursa of the foot which cannot be visualized in any other way. Not only does MRI allow us to diagnose more accurately, but it allows us to monitor the progression of conditions and carefully assess the horse’s response to treatments.

X-ray imaging is used to assess bone pathology as an initial tool. However, it can take up to 2 weeks following injury before the bone pathology is noticeable on radiographs, and sometimes it is not visualized at all.  MRI is the only imaging modality that can assess inflammation within bones such as bone bruising or cysts. These can cause severe lameness and require long periods of rest but would not be diagnosed without the use of MRI.

As equine vets we are eternally grateful for these advancements in technology which have enabled us to achieve an accurate diagnosis much faster than ever before, and as we know, a faster diagnosis leads to more precise treatment and management protocols to get your horse feeling in tip-top shape again.

What is kissing spines and why has it suddenly become more common?

Kissing spines or more correctly termed ‘impinging dorsal spinous processes’ (IDSPs) is where there is over-crowding of the summits of the 18 spines that the horse has, usually in the saddle region of the spine. This leads to bone friction and pain which spreads along the muscles either side of the spine. In our years of experience of dealing with this disorder, by far the most common clinical signs are (in order):

1. Bucking
2. Being ‘Cold-backed’ on mounting
3. Hunching or arching of the spine
4. Sudden shooting/scurrying under saddle particularly on mounting
5. Bolting

Yes, some young (and old!) horses will buck when they are excited, these horses usually have their ears pricked and they are ready to go!! Horses who buck due to pain will have their ears pinned back and they are not ready to go, they just want to get rid of the pain (unfortunately that’s usually the rider on board!).

The problem we have in diagnosing this condition is that many horses will have kissing spines on X-rays of their spine, in fact up to 86% of thoroughbred horses will have x-rays consistent with IDSPs! That does not mean that they are all painful! To determine whether or not the x-ray findings are causing discomfort relies on 3 methods of diagnosis (in order of our preference!):

1. Medication of the spine with steroids (potent anti-inflammatory drugs) which lasts several weeks in this region in severe cases, so you can tell if your horse feels better over this prolonged period of time.
2. Infiltration of the spine with local anaesthetic and seeing if the clinical signs resolve when the horse is re-evaluated ridden.
3. A ‘bute’ trial, whereby we administer systemic anti-inflammatory drugs to see if the clinical signs improve.

Only then can we be sure if the X-ray findings are consistent with pain in the horse. So your horse is diagnosed with kissing spines, what can we do? Is it hopeless? NO, in fact, this condition can be treated fairly successfully in most cases either with conservative management and altered training techniques, including physiotherapy or with different surgical methods. If your horse is suffering with kissing spines, we are equipped to help you every step of the way with your journey back into the saddle.

And in answer to the original question, IDSPs is NOT more common than it was years ago…….we just have X-ray machines that are capable of seeing the spine now. We are also more aware than ever that our horses are generally not a naughty bunch, and are often just asking for our help because something hurts!