Your horse needs to be able to shelter from the heat, cold and rain. A three-sided shelter / run-in shed will work very well. The flooring of the shelter should be dry and the walls should be strong and hazard-free.
If your horse is kept in a stable make sure you provide adequate bedding (e.g. straw, hemp) and keep the stable clean by following a daily mucking-out routine.
You should feed your horse a minimum of twice a day. Get veterinarian advice on the most suited feeding program for your horse.
Ensure that a fresh water supply is available to your horse at all times. A healthy horse can drink up to 12 gallons of water per day.
Your horse will also require vaccinations, dental examinations and de-worming treatment. Seek veterinarian advice for a suitable health care program.
Worm Egg Counts
A targeted approach is the right approach
Dr Emma Batson of Merial Animal Health explains why it is increasingly important to monitor the worm burden of your horse and how a targeted approach to worming is vital for all horse owners.
We now know that the level of worm infestation can vary considerably from one horse to another – even those kept together on the same yard. As a general rule, it is estimated that 80% of the equine worm population is carried by only 20% of horses, so clearly a blanket approach to worming may be unnecessary for the majority of horses.
Targeted programmes incorporating faecal worm egg counts (WECs) play an important role in managing equine parasites, reducing unnecessary treatments so that each individual horse is only treated as needed.
WECs are easy to undertake, simply take a fresh sample from each horse, send them away to be analysed by your vet or laboratory and the results will be returned, along with a recommendation of whether worming is necessary at that time. WECs are a vital part of EQVALAN®’s SMART worming campaign, which encourages owners and yard managers to Simply Monitor, Assess Risk and, if necessary, Treat with the most appropriate wormer. A simple to use online planner at www.smartworming.co.uk takes the guesswork out of worming.
Target tapeworms too
WECs are a great indicator of most species of adult roundworms; however, immature and encysted small redworm cannot be detected on a WEC test. Tapeworms can only be properly detected with a blood test. Research has shown that tapeworms are associated with certain types of colic and so in the absence of a blood test, it is important to treat these parasites with the right product at the right time.
Whilst traditionally a double dose of pyrantel-based wormer was the only treatment available for tapeworms, more recent developments mean that a single dose of combination wormer such as EQVALAN® Duo which contains both ivermectin and praziquantel – a known tapeworm treatment – is all that is needed.
Twice yearly treatments for tapeworm in the spring and autumn will act as the cornerstone of your programme. So just one dose, twice a year, will help keep the tapeworm burden at bay. An annual treatment for immature and encysted small redworms is also usually recommended during the winter months, and in between times regular WECs recommended every 8-10 weeks can be performed.
The combination of twice yearly tapeworm treatments, an encysted treatment and regular WECs will provide optimal results for all horses, reducing the amount of wormer required as well reducing the threat of worm resistance.
Find out more at www.smartworming.co.uk
Providing a Faecal Sample for Worm Egg Counts
- Collect dung from each animal to be tested – do not combine dung from several animals. Fresh dung is of paramount importance as worm eggs can begin hatching shortly after collecting and this can make your WEC (worm egg count) result inaccurate.
- Collect 3 – 4 boli from various places in the dung pile. Mix them together in a bag and then take a smaller sample from this for the WEC – a small handful is plenty.
- Place this small sample into a small bag, and then the small bag into a larger bag. Ensure the larger bag is labelled with the horse’s name, your surname and the date the sample was collected (you might want to do this before you place the sample in the bag!).
- Keep the sample out of direct sunlight and in a cool place. If you cannot deliver or post the sample immediately, keep it in the fridge, but aim to send or deliver the sample on the day of collection.
- Your WEC result will usually be ready within 2 days
What is Wormer Resistance?
Anthelmintic resistance occurs when a proportion of the parasites picked up from a particular pasture are no longer affected by the chosen worming treatment. A number of factors can contribute to the development of resistance, including underdosing and the frequent, perhaps unnecessary, administration of wormers over time.
All worms in any given population (i.e. inside a horse) are each as genetically different from each other as humans are genetically different from one another. A very few of those worms will have a natural genetic variation that can enable them to survive a dose of anthelmintic, or wormer. This sort of variation exists within all populations of all organisms. This occurs partly because random mutations occur in the genome of an individual organism, and these mutations can be passed to offspring. Throughout the individuals’ lives, their genomes interact with their environments to cause variations in traits. The process of natural selection, as detailed by Charles Darwin’s theory of evolution, states that those living things that are the best adapted to survive in their environments will survive and be the most successful at reproduction, therefore having more offspring, which also have the genetic mutation. Eventually, through natural selection such mutations become the norm.
How does wormer resistance develop?
Using too low a dose of wormer is one of the key ways that helps those slightly, naturally resistant worms to survive. These then breed with each other to potentially produce a higher proportion of resistant worms and a -smaller population of susceptible worms within the population. Successive doses of the same wormer, or wormers from the same drug class, can lead to an established resistant population.
Frequent, unnecessary worming can also increase the potential for resistance, by actively selecting for worms that are resistant and killing out susceptible worms before they can reach sexual maturity and produce off spring.
Once resistance is present in a worm population, the health, welfare and performance of those horses infested with resistant worms will be compromised. It is also impossible to revert back to a susceptible population.
Reducing & Preventing Resistance
The key to reducing the likelihood of resistance developing starts with the identification of those horses which need to be treated. This can be achieved by testing individual horses, thereby identifying those animals with a significant worm burden, and then using the correct wormer to treat them – calculating the correct dose and time to worm.
Worm egg counts help to ensure that wormers are only given when they are needed and therefore may reduce the likelihood of resistance developing. This helps your individual horse and the equine community as a whole.
As part of this more targeted approach to worming, industry experts are calling for horse owners to make better use of Worm Egg Counts (WECs). A WEC is a microscopic examination of a dung sample from a horse to detect and count the number of roundworm eggs present. The egg count is expressed as eggs per gram (epg), and in most cases if the count is greater than 200epg then worming should be considered (some foals and horses, especially where there is no previous worming history, may still require treatment where the worm egg count is less than 200 epg; consult your vet for further advice). A WEC therefore helps to identify those horses that have an excessive worm burden and would benefit from a treatment. It also identifies the main species of worms with the exception of tapeworms, and immature and encysted worms.
It is known that approximately 80% of worms are carried by only 20% of horses. The regime of regular worming at fixed intervals, a system that has traditionally been popular on large yards, has provided an effective means of limiting worm burdens, but it is possible that many horses are being wormed unnecessarily, which encourages the development of resistance. With the consensus of expert opinion on the future of worming firmly behind the use of targeted programmes incorporating WECs, there has never been a better time to make worm egg counts a regular part of your worming programme.
Keeping track of treatments and WEC results may seem like an onerous task, however Merial’s online SMART planner reminds you when to test and worm accordingly, helping you to keep track of every horse in your yard if required.
Find out more at http://www.smartworming.co.uk
Laminitis is a disease of the feet of hoofed animals (‘ungulates’), most commonly affecting horses and cattle. Classic signs in horses suffering from laminitis are lameness and heat around the affected hoof. The disease is one of the most common causes of lameness and can even be fatal The condition is primarily an inflammation of the digital laminae of the hoof, for which there are a number of causes.
In order to protect against laminitis owners must make themselves aware of the causes and symptoms associated with its early stages. Early diagnosis is critical in getting a full recovery.
What is Laminitis?
Laminitis is Inflammation of the digital laminae of the hoof that supply and contains a network of capillaries and nerves that together act to nourish and secure the coffin bone to the hoof wall. As all of the horse’s weight is resting on these four hooves, which are also acting as shock absorbers during locomotion, the blood supply must be optimal in order to maintain fitness. When the blood supply to laminae is compromised due to this inflammation, the laminae can become progressively detached from the coffin bone causing sinking and/or rotation of the bone within the hoof.
What causes Laminitis?
The possible causes of Laminitis are extensive, and relatively poorly understood. Broadly speaking they can be split into either mechanical or systemic causes. Mechanical causes would include any injury associated with an external element, whilst systemic causes are associated with nutrition, blood supply, or other internal factors.
Mechanical laminitis occurs when the hoof wall is pulled away from the bone or lost entirely through excessive or persistent trauma. External injuries that damage the hoof wall significantly enough to affect the underlying digital laminae are also known causes, but are rare.
Systemic laminitis usually affects two feet, and although it can affect all 4 feet it typically affects the front feet. Systemic Laminitis can lead to rotation or sinking of the coffin bone placing undue pressure within the hoof capsule, leading to abscesses which can be severe, very painful, and difficult to treat.
Currently there are three main hypotheses for mechanisms that may result in laminar failure.
- Classical inflammation: This includes infiltration of potentially destructive white blood cells. It is suggested that this is caused by a carbohydrate overload, either by an excessive grain intake or pasture that is under stress and has excessive sugars in it. The horse may be unable to digest all these carbs in the foregut, moving into the hindgut and fermenting in the cecum. This results in endotoxins being absorbed into the blood stream and which leads to whole body inflammations. In the feet this can lead to damage to other tissues as there is no expansion space for inflamed tissues and laminitis resulting. An example of such would be laminitis following colic, or a retained placenta in a mare after foaling.
- Ischemia-reperfusion injury: This is injury to tissue at a cellular level caused by a loss of blood supply and oxygen followed by an influx of blood and oxygen. Researchers have seen both decreased and increased blood flow to the laminae in laminitis cases and as ischemia-reperfusion injury includes both, it has been widely researched as a cause for laminitis. It is still unclear what the trigger factors are for ischemia-reperfusion injury in laminitics.
- Equine Metabolic Syndrome: The result of a long term lifestyle of being overweight which changes the way the metabolism handles glucose and insulin. This in turn leads an increased risk of becoming insulin resistant. Insulin resistance prevents glucose being taken up by the lamellae and they become weak, and prone to collapse or detachment. Horses with EMS are more likely to be prone to laminitis as a result of lush spring grass or frozen grass due to the higher concentrations of fructans.
How will your vet diagnose Laminitis?
Treating the condition effectively is dependent on getting an early diagnosis. External physical symptoms are not very specific and can be attributed to other possible issues. Veterinary examination may be enough to diagnose the condition but radiographs are a useful diagnostic tool in ascertaining the severity of the disease.
- In horses where just the front feet are affected the horse will adopt the classic “founder stance”: the horse will bring its hind legs underneath its body to take the weight off the front legs and put its forelegs out in front, called “pointing”.
- In horses where all 4 feet are affected the horse will often shift weight from foot to foot trying to relieve the pressure
- Increased temperature of the wall, sole and/or coronary band of the foot.
- A pounding pulse in the digital palmar artery. (The pulse is faint to undetectable in a rested horse, but is clear after hard exercise.)
- Visible trembling
- Increased vital signs and body temperature
- Flared Nostrils
- Walking very gingerly, as if on egg shells
- Lameness, and an unwillingness to move at all
- Tendency to lie down and if severe, to remain lying down.
A radiograph can give useful information concerning the severity of the condition including degree of rotation, sole thickness, measurement of the dorsal hoof wall thickness, and vertical deviation.
What Treatments are available?
Clear distinctions must be drawn between acute and chronic laminitis cases, as their treatment and management needs will differ. Please discuss with the practice if you have any concerns about your horse or pony.
How can I prevent my pony getting Laminitis?
- Prevent carbohydrate overloads – keep feed rooms locked, keep pastures grazed tightly, or split fields into smaller paddocks
- Don’t allow young stock to become overweight as this will increase the risk of the pony developing insulin resistance with consequences later in life.
- Body condition score your horse every two weeks. Horses tend to gain weight in the summer and lose it in the winter. With rugs, stabling, supplementary grain and forage, feeding horses rarely lose condition in the winter time, but still gain weight in the spring. Your horses’ body condition score through the spring and summer should be ~4-5, in winter ~3-4. Further information can be found at http://www.saracenhorsefeeds.com/condition-score
- Ensure he/she has plenty of forage. If you need to reduce his calorie intake don’t reduce the quantity of forage, simply soak it for 12hours which will leech out the sugars and reduce the calorie content.
- In brood mares especially ensure that the diet is balanced in terms of vitamins and minerals. Suboptimal nutrition in mares has been shown to increase the risk of insulin resistance in foals.
- Manage grass intake by either:
- Fitting a grazing muzzle. This not only reduces the quantity that is consumed but it has also been shown that ponies with grazing muzzles will walk up to 5 times further during turnout than non-muzzled ponies.
- Grazing with more horses or ruminants.
- Reduce paddock size.
- Top fields once/week.
- Turnout in a sand school with soaked haynets (in the chronically obese where all the above strategies have been exhausted or are unfeasible).
- Provide the horse with daily exercise to raise the HR (80bpm in active walk) for a minimum of 30 minutes
- Remember that only horses that are working need additional bucket feeding. Horses or ponies that do not break a sweat when ridden should not require additional bucket feeding.
- Overweight horses are a welfare concern just as much as thin horses.
- Parker, S, 2013, Laminitis & Founder. Available at www.parkerfarrierservice.com/laminitis_founder Date accessed 01-07-2013
- RVC, 2013, Research News, available at: http://www.rvc.ac.uk/Research/News/Laminitis.cfm. Date accessed 01-07-2013
- Pollitt, C et al, 2003, “Equine Laminitis” (PDF). Proceedings of the AAEP 49 at http://www.ivis.org/proceedings/AAEP/2003/pollitt/IVIS.pdf Date accessed 02-07-2013
- McAllister et al, 1993, Comparison of Adverse Effects of Phenylbutazone, flunixin megalumine, and ketoprofen in horses, JAVMA, 202 (1).
- Doucet, M, et al, 2008, Comparison of efficacy and safety of paste formulations of firocoxib and phenylbutazone in horses with naturally occurring osteoarthritis, JAVMA, 232(1)
Strangles is a widespread, highly infectious, debilitating disease of horses. It is caused by a bacterium called Streptococcus equi. Strangles is considered to be the most commonly diagnosed infectious disease affecting horses of all sizes, breeds, types and ages, although some groups are higher risk than others and may be the worst affected – young horses (<5 years old), sick horses, horses with compromised immune systems, (what are herd horses?), stud farms, racing stables, livery yards and riding school horses. This is due to the way the disease is spread. Direct contact between horses is the most common factor, but spread of the disease is also via contaminated food, drinking vessels or equipment including people’s clothing. The disease can be spread by inhalation but this is less common.
Strangles is not a notifiable disease, but yards with confirmed outbreaks are strongly recommended to implement stringent biosecurity precautions to prevent further spread, and to notify neighbouring premises.
The severity of clinical signs can vary depending on the age and condition of the horse. Clinical signs are usually seen between 3-7 days after the horse has been in contact with the bacterium, but can take as long as 14 days to show.
Clinical signs include:
- Loss of appetite
- Difficulty in swallowing
- Nasal discharge
- Depression and dullness
- Development of a cough
- Swelling of the lymph nodes (glands) under the jaw or lower down the neck approximately a week after the onset of clinical signs.
- Complications seen in a small number of rare cases include:
- Abscesses placing pressure on the airways, causing the horse to suffocate – hence the term ‘Strangles’
- ‘Bastard Strangles’ causes swelling of lymph nodes in other areas of the body such as the brain, lungs and/or intestines can occur. Rupture of these abscesses is usually fatal.
- Purpura haemorrhagica which causes bleeding into the skin, gums and organs such as the lungs and can also prove fatal.
When the abscesses in the lymph nodes burst they discharge a highly infectious, thick creamy-yellow pus.
Atypical strangles is now a commonly recognised condition of infected horses that display lesser or even no clinical signs. Such infected animals may show a mild respiratory infection but without developing abscesses. These horses may not be recognised and therefore go untreated. It is unknown just how many horses are latently infected in this way and it may be that they represent a significant majority of the total number of horses affected. Most horses infected with Strangles recover uneventfully over a period of 3-4 weeks but this depends on the severity of the symptoms, and the immune system of the affected horse. More severe cases may take longer to make a full clinical recovery. Some horses can remain as infectious carriers for many years even though they appear to have made a full recovery.
Spread of Infection
The disease is spread when the nasal discharge or material from the draining abscess is passed from direct contact between horses or contaminates the environment
For example, the infection can be spread:
- by nose to nose contact between horses
- via equipment shared with infected horses, such as:
- water troughs where the bacterium can survive for long periods
- feed buckets
Horses that appear healthy are easily overlooked when investigating a case of strangles. It is important to remember that
- There is a delay of between 3 and 14 days between horses becoming infected and showing clinical signs
- Horses can shed disease (i.e. pass it to others) before showing clinical signs of the disease
- Horses with atypical strangles will not show any clinical signs but are still infectious to others
- Horses recovering from the disease can still be infectious for many weeks. Untreated horses (not given antibiotics) will shed the bacteria on average for 2-6 weeks after infection.
- Carriers can remain infectious for months or years
The diagnosis is relatively straightforward in horses that develop classic signs and is confirmed by taking a swab from the back of the horse’s nasal cavity (nasopharynx) or by directly swabbing a draining abscess. The more challenging cases are those which only develop a nasal discharge without the classic lymph node enlargement, as this can resemble other, less serious bacterial respiratory diseases.
We recommend isolation of any horse that develops a thick nasal discharge and taking nasopharyngeal swabs for culture to check for strangles bacteria. An unusual form of strangles is recognised which produces flu-like symptoms and often becomes persistent in a yard. Reaching an early diagnosis in these cases is very difficult as the clinical signs demonstrated are non-specific and consequently a large number of horses may be affected before a diagnosis of strangles is reached. Recently a new blood test has become available to identify if new horses entering a yard have previously been exposed to the infection or to monitor any long standing infections. We do not recommend use of the blood test as a diagnostic tool in acute outbreaks.
There are currently three tests available which can be carried out by your veterinary surgeon:
- A blood test available at the Animal Health Trust (AHT)
The blood test identifies antibodies to the S. equi antigens in the horse. In practice the blood test is used to identify both carriers and recently infected horses with a 90.9% sensitivity and because it requires only one blood sample, it is easier and more convenient for veterinarians to routinely screen horses prior to movement, competition or sales. If the test is positive the horse is likely to have been in contact with strangles in the recent past. Further tests are then required to confirm if the horse is recovering from the disease or is a carrier.
It is important to note that it takes approximately two weeks for a horse to develop antibodies against each antigen and so it may not be possible to accurately identify horses that are incubating the disease or are in the early stages. The test is particularly useful as a screening tool prior to movement or introduction of a horse into a new yard?, and in the identification of potential carriers at the end of a strangles outbreak. The new blood test should result in more rapid diagnosis as the results can be obtained within 24 hours of receipt of the sample by the AHT, and only one sample is needed.
- Guttural pouch endoscopy including bacteriological analysis of guttural pouch washes.
This test is most useful in horses that have already developed classical signs and diagnosis is simply confirmed by swabbing from the back of the horse’s nasal cavity (nasopharynx) or by directly swabbing a draining abscess. This material is then cultured for the bacteria.
- A series of three clear nasopharyngeal swabs, taken at weekly intervals, testing for the presence of the bacterium.
This test is most useful in confirming that the infection has been resolved.
A few horses, following infection with the disease, can become chronic carriers. These horses harbour a reservoir of the bacteria in their guttural pouches, frequently in the form of chrondroids (balls of dried pus). Such horses show no clinical signs of the disease and appear perfectly normal and healthy.
It is interesting to note that many outbreaks of strangles occur after the introduction of apparently healthy animals to a yard. Approximately 10% of horses infected with Strangles become carriers even though they themselves have recovered and appear clinically healthy and normal. This effect is more common in those horses that have not received any treatment (antibiotics). It is unknown how long a horse may remain a carrier, although trials have shown the bacteria can survive for more than five years.
Should infection be diagnosed, or even if it is just suspected before a confirmed diagnosis can be made, then all relevant animals should be isolated. This includes:
- Infected horses
- Suspected infected horses
- All horses that have been in contact with the above two categories
Isolation is a critical step in preventing further disease spread. The ‘Strategy to Eradicate and Prevent Strangles (STEPS)’ provides detailed information on isolation and can be found on the following link:
Yard owners should implement a strict quarantine procedure for new arrivals to the yard, not just for Strangles risks, but also for worming, influenza, and ectoparasites. A clear blood test (for Strangles) can be requested before accepting a new horse on to the premises.
Yard owners are also strongly advised to consider biosecurity management plans in the event of an outbreak. It is critical that rapid isolation of infected and at risk animals takes placeto prevent further spread of the disease. Adelay whilst this is researched and understood could mean the difference between movement restrictions on the yard for a few weeks or for many months. Strict hygiene and biosecurity plays an essential role in preventing and controlling this disease.
Treatment varies for each individual case. Individual treatment protocols should be discussed and agreed with the attending veterinary surgeon. The speed and success of resolving cases often hinges on the strict management of isolation, quarantine, minimising movements (of people and horses) and disinfection.
Please contact your practice vet for further information.