In the middle of summer or when fall is almost around the corner, flies may hover around a dog's ears and start feeding on the tissue causing a hard to get rid of irritation.
Common flies involved in this process are the common stable flies, black flies, deer flies and the all to well known house flies. These continuos biting cycle is called "Fly strike" and it seems to occur the most in outdoor dogs that live nearby stables or livestock.
THE FLY STRIKE DYNAMIC
Affected dogs will show typical red sores all around the rim of their ears. Some breeds with erected ears are preferred by these flies because of the easy accessiblity. However, floppy eared dogs are not disliked, having their front edge of their ears affected.
A dog's ears are their preferred bite site because the skin is much thinner on the ears and because the dog cannot really do much to defend it's ears. Also, in some cases a dog's ears can be affected by minor cuts, sunburn or even smelly ear infections that will greatly contribute the fly population to feast on them. In some severe cases however, the flies will also bite the nose areas.
To make things worse, once flies start biting the wound, further flies will be attracted and the dog can be bitten even hundreds of times a day. These bites can be very painful and cause the dog to start scratching the site further worsening the problem. Should the wounds be attractive enough, some flies may then decide as well to lay some eggs allowing maggots to appear within a short period of time, usually between 8-12 hours.
KEY SYMPTOMS OF FLY STRIKE
Bloody tips of ears in erect eared dogs
Bloody front edges in floppy eared dogs
Crusty areas on ear once blood dries out
Dogs pawing and scratching at ears
Presence of flies around ears
Damaged or scarred tissue around ears
GENERAL FLY STRIKE (MYIASIS)
There is a more serious and even life threatening form of life strike which is also known as "Myiasis". It can be seen in sheep, horses, deer, cows and even outdoor dogs and cats. This form affects extensive body parts and is seen mostly in incontinent dogs or dogs affected by diarrhea. The flies (in particular the bot fly) will feed on wounds or create new wounds that will further attract other flies. Eggs will shortly thereafter be deposited and maggots will grow within 8-12 hours. In severe cases the flies will bite through the skin and layers of muscles and in some cases feed up to the spine. The eaten up areas can look horrendeous and can be masked by long hair. Death can occur within 3-5 days due to fluid loss, protein loss and inflammation.
PREVENTING FLY STRIKE
Prevention is primary based on eradicating the fly congregations. There are some good fly repellant products and/or sprays that can help prevent the flies from returning.
It is a very good idea to practice good hygiene to prevent the flies to return. Clean your dog, remove mats and remove any fecal matter stuck behind. Keep sick, incontinent dogs away from fly infested areas. Clean up the living areas of your dog. Take away feces,urine, trash, or anything known to attract flies. Keeping the dog indoors may be a good permanent solution.
TREATMENT
At home the affected areas could be washed with lukewarm water and a good antispetic soap.
After a good cleaning, a good triple antibiotic ointment as Neosporin can be applied to the affected areas.
In mild to severe cases a veterinarian should be consulted. The ears may need to be cleaned and disinfected under sedation or general anesthesia. In general fly strike maggots will need to be carefully removed and fluids may need replaced if dog the is dehydrated. Antibiotics may help the wounds heal and antihistamines or even corticosteroids may be prescribed to reduce the inflammation involved. Severely affected dogs may need to be hospitalized.
Fly strike can be a very annoying issue to deal with. Once the fly biting and itching cycle gets started it is hard to get rid of. It is much easier to prevent flies from being attracted to your dog's ears rather than trying to defeat them once they have established.
Practice good general hygiene, keep your dog and it's ears clean and if possible keep him indoors especially during summer heat peak hours.