With record high temperatures forecast over the next few days, it is important to ensure your horse or pony is well hydrated and able to cope with the heat.
Here is some useful management advice to consider during the heat of the summer months.
Horses’ water intake increases considerably during hot weather and if several horses are turned out together, it’s advisable to provide more than one source of clean water so that dominant horses can’t prevent more timid ones from drinking.
When travelling and competing your horse or pony, always take plenty of fresh water. If you are going on a long journey, make sure you stop regularly to offer your horse a drink and to check that the horse is not overheating. For those that don’t drink well, consider adding apple juice or peppermint cordial to flavour the water to increase their water intake.
Electrolytes are minerals (sodium, potassium, chloride, calcium, and magnesium) that dissolve in the blood and tissues of the body to create a ‘salt’. They help to preserve the correct balance of fluids in the body’s cells and are involved in muscle function and the processing of wastes. Electrolytes are lost daily through sweating, in urine and in faeces and those losses will increase significantly during exercise or competition, especially during hot weather. Deficiencies cause dehydration, impaired performance and may exacerbate clinical problems such as azoturia (tying up). Adding an electrolyte supplement to your horse’s diet will encourage him to drink and help to restore any electrolyte imbalances caused by sweating associated with exercise or travel. After a period of excessive sweating it may take several days of electrolyte supplementation to completely replenish losses. However, electrolytes should not be fed in large amounts if the horse is not fed these regularly. It is recommended initially to add 50g of a balanced electrolyte split between two feeds, or in water (N.B. follow label instructions to avoid overfeeding electrolytes). Some horses may not drink water containing electrolytes, so plain water should also be made available. Electrolytes can also be administered in pastes, which can be useful if given at or after a competition.
Allow horses access to a salt block or to receive a daily salt supplement (no more than a tablespoon per day) to allow them to meet their dietary sodium chloride requirements.
When temperatures suddenly rise, horses will not be acclimatised to working in those conditions and preferably should not be worked during the hottest part of the day. Try to exercise your horse early in the morning or later in the evening, when temperatures are lower than during the middle of the day.
The same applies when travelling – trailers and lorries can become extremely hot, particularly if they are standing stationary in traffic. Unless you have air conditioning or a cooling fan in the horse area of your lorry, your horse can become overheated and dehydrated in a short period of time. During long journeys, horses should be checked and offered water regularly to prevent them overheating and becoming dehydrated. If you have to travel your horse in hot weather, set off early when it is cooler and when you are less likely to get stuck in traffic. Professional transporters in the UK aren’t permitted to move horses when the temperature exceeds 30°C and it’s recommended that private owners should follow this. On arrival at a show or event, consider whether your horse will be cooler off the lorry or trailer than left standing on it.
Take plenty of fresh water from home when travelling or competing as some horses don’t like water that tastes different.
When competing in very hot conditions, allow a shorter warm-up period and be prepared for your horse to tire more quickly. Offer water after warming up, before competing and immediately after competing to reduce the risk of heat related health issues. Adrenaline will also be higher in hotter conditions and horses that are working hard and sweating for prolonged periods will be more at risk from heat stress, dehydration, electrolyte imbalance and muscle damage.
Use plenty of cold water to cool horses down after exercise, applied by a hosepipe or using sponges and buckets. Using a hosepipe or buckets of water with ice added will have a greater cooling effect and will lower the horse’s body temperature more quickly. Studies have shown that if you are using cold water (15 degrees or less, 5 degrees is ideal), it doesn’t need to be scraped off for it to be effective in cooling the horse, particularly horses exhibiting signs of heat exhaustion/heatstroke: it is more important to continuously apply cold water all over the horse’s body and it may be 10-15 mins before you see any effect. It is recommended that the horse be walked for short periods until it has cooled down in order to prevent muscle spasms.
Heat stroke, also known as heat exhaustion or hyperthermia, can occur when horses work in excessively hot or humid conditions and is a condition that must be treated immediately. Body temperature can rise dangerously due to massive heat production from the muscles, insufficient heat loss, excessive loss of fluids and electrolytes, and oxygen being consumed faster than it is being delivered. The consequences can be serious and sometimes fatal.
Common causes of heat stroke are:
Signs of heat stroke are:
If your horse displays any of these signs during periods of extreme heat, it is important to use aggressive cooling methods to reduce the horse’s temperature and to call your vet as it might be necessary to administer intravenous electrolytes. Severe heat stroke can lead to collapse, renal failure, muscle damage, liver damage and laminitis and can be fatal if not treated immediately. Always seek veterinary help if you suspect a case of heat stroke.
It is important to provide adequate shelter with good ventilation to protect your horse or pony from the heat and biting insects. Many horse owners will bring their horses in during the day during the heat of the summer and turn them out at night when it is cooler. Ensure the stable has good ventilation and is as free from dust as possible. If you don’t have access to a stable, ensure there is adequate shade in the paddock, either from trees or by providing a field shelter.
Horseflies and other biting insects can be a big problem at this time of year and it is important that horses are offered some protection from these with fly rugs, masks and insect repellent. Use a well fitting rug that it is lightweight, breathable and light in colour to reflect the heat. Ensure fly masks are fitted correctly and don’t rub or make contact with the horse’s eyes.
It is important to remove manure from fields regularly, not only to prevent worm contamination but also to discourage flies.
Horses with areas of pink skin are susceptible to sunburn and these areas (frequently on the face and limbs) require a high factor sun protection cream to be applied regularly to prevent redness, blistering, discomfort and peeling. In severe cases where skin is blistered or raw, seek veterinary advice.
Taking affected horses out of the sun is key, as is addressing those areas that have been burnt. If the sunburn is mild, discomfort can be soothed by moisturising the dry skin and using products such as aloe vera gel. Occasionally, the sunburnt area may become secondary infected and your vet may prescribe a topical antimicrobial cream to help limit infection and soothe the skin. To prevent further sunburn, consider turning your horse out at night, or in a field with plenty of shade to stand under.
Repeated skin damage can possibly lead to longer-term problems: thickening and scaling on the surface of the skin (keratosis), which can sometimes transform to skin cancer.
Masks that cover the head and muzzle may provide some relief and fly protection rugs can help shield horses with more widespread sensitive areas.
Sunburn can also be a result of photosensitisation. This is an abnormal reaction to sunlight when a ‘photodynamic agent’ such as a plant, chemical, fungi or bacteria in the skin is present in the horse’s circulation due to ingestion or absorption through the skin. Primary photosensitisation is caused by ingestion of chemicals from particular plants, such as St John’s Wort. These chemicals settle in the skin where they react to UV light, making the horse’s skin susceptible to burning. Sunburn can also occur as a result of liver disease in horses (secondary photosensitisation,) where toxins normally processed by the liver sensitise the skin to UV light, often resulting in severe and widespread sunburn. The difference between these different types of sunburn will require veterinary diagnosis.
If you have any concerns about heat-related health issues in your horse or pony, contact your vet immediately for advice.