Have you got the Fly Spray?

March 2020

We have all experienced the irritation flies and midges create, from buzzing around our horse and ponies to actually landing on them. In some cases, insect bites leave our horses with unwanted lumps and bumps due to their body’s natural reaction to defend them from foreign attack.

The common question asked is ‘Which fly spray do I use?’ In truth there is no simple answer. It is important to have a product that is legal, safe and effective. After that it is down to personal preference, both for you and your horse. However, there are a few key indicators to look for when choosing your horse and pony’s relief from fly fury.

Firstly, it is important that your product is legal. All equine fly repellents are regulated under UK law and must be either approved or authorised. The purpose of this is to protect you, your horse and the environment. A legal fly repellent product with have an approval number such as ‘HSEXXXX’ or an authorisation number such as ‘UKXXXXXXX’ displayed on the label. This registration ensures you are using active ingredients known to be effective, and products whose safety is monitored. So, checking your product is legal is important for equine welfare. There are many products on the market, some of which are illegal and even unsafe for use on horses.

COMMONOLY KNOWN INGREDIENTS

DEET (Di-ethyl-m-toluamide) is one of the most well-known active ingredients for fly repellents, formulated for use by US soldiers during testing times in the jungle in 1946. It is not exactly understood how DEET actually works, but recent research has suggested that DEET masks the odours emitting from our skin by reducing their volatility. Different companies include different active ingredients at different concentrations. Generally, the higher the inclusion rate of the active ingredient, the more effective the product. NAF have commissioned several studies on equine fly repellents involving DEET and believe that at concentrations around those found in NAF OFF DEET Power Performance products that is one of the most safe and efficacious products on the UK market. It is important to understand that DEET repellents designed for use on people may not be safe or legal to use of your horse.

Eucalyputus citriodora oil is a natural derived oil with proven insect repellency. This active ingredient is found in NAF OFF Extra Effect products. At the levels found in NAF OFF Extra Effect Spray, this product is safe to use of horses and a popular natural choice for many.

Permethrin and Cypermethrin are active ingredients found in some equine fly repellents on the US market. These products are not approved for topical application to horse other than as approved by the Veterinary Medicines Directive, due to their high toxicity. Permethrin and Cypermethrin work by targeting the nervous system and creating paralysis or worse when the insect lands. Both compounds are toxic to both fish and cats, so caution would be advised when using around your horse – particularly if your yard relies on an efficient feline ‘mouser’ for rodent control.

Citronella oil has traditionally been used as an insect repellent, however it’s legal status as a repellent has never been established in terms of efficacy and safety, and therefore no product based on citronella oil can be marketed as a fly repellent. This marketing ban has led to confusion with some people thinking it is banned for competition use, but that is not the case. NAF OFF Citronella products are safe and legal to use, both generally and under FEI rules – they simply can’t be marketed as a fly repellent.

The same applies to a number of other traditional essential oils, and this sometimes leads to riders experimenting with homemade fly repellents, however this is something we would strongly advise against. Essential oils, in particular, can be very aggressive, causing severe reactions on some horses, dependent on both concentration rates and how they have been combined. Many contain skin sensitizer to which you or your horse may react. Some are even harmful to the environment. Therefore, we advise those looking for an equine fly repellent it is best to trust the professionals and buy a commercial solution. The NAF OFF Range still advise a small 24hr patch test is carried out before general application of any new product, simply due to the unpredictable nature of allergies.

In terms of the best application method, a spray is usually the most effective in terms of coverage and easiest to use. However, some horses do not like sprays and so creams and lotions are also available. Using a sponge with these can be effective, but, it is much more difficult to achieve the desired level of coverage. Caution must be taken around the more sensitive areas which have little covering of hair such as between the hind legs and around a mare’s teats who may be feeding a foal at foot. Remember, if using a sponge or cloth, to choose one made of natural fibres, if using a DEET based product. While DEET is proven to be safe for application to skin and natural fibres, it will attack some plastics and manmade fibres. For the same reason, if decanting your DEET based spray from a larger bottle, always decant into a dedicated DEET fly repellent spray bottle, as other spray bottles may not be suitable.

When you are next asked the question, “Have you got the fly spray?” whether you are going to a competition or simply riding at home, take into account what is in your fly spray and follow the advice on the packaging.