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10 Way Deer-flies and Horse-flies Affect Human and Pets


Significantly larger than the common house-fly, these insects can wreak havoc not only to your weekend getaway but also your health, pets, and livestock. Listed are 10 ways that Deer-flies and Horse-flies can affect humans and pets, and below are some ways to prevent them.

1- Unpleasant Outdoor Life

Deer and Horse-flies are visual hunters. They tend to prefer sunshine, and this can make outdoor life unbearable depending on the number of flies in the area.

2- Painful Bites

Female Horse and Deer-flies are anautogenous, which means they need the protein from blood to produce eggs, so they primarily feed on mammals. Their bite can be extremely painful as they make a cross-shaped incision with their mandibles and then lap up the blood that pools there.

3- Allergic Reactions

Female Horse and Deer-flies also excrete an anticoagulant after biting to prevent the blood from clotting, but this can possibly lead to severe allergic reactions. Most symptoms diminish after a few hours, but some reactions can include a rash, hives, wheezing, dizziness, and swelling around the eyes or lips.

4- Infection

It is possible, that if not left alone, a bite could become infected. If this happens, it is important to seek medical attention.

5- Diseases

In addition to allergic reactions, these flies can transmit diseases through their bite. These can bacterial, viral, or parasitic diseases and can affect both humans and animals.

6- Reduced Milk Production in Cattle

A common problem with cattle, when bitten frequently by these flies, is that their milk production can be reduced.

7- Grazing Interference

Cattle and horses tend to bunch together when under attack from incessant biting. This can lead to interference in their grazing patterns.

8- Bodily Harm

When trying to get away from those painful bites, injures can occur to humans, but especially to animals as they are more focused on their escape than their surroundings.

9- Difficulty in Controlling Populations

Eggs are typically laid in damp areas, and most insecticides cannot be sprayed near delicate wetlands.

10- DEET Not Reliable

Spray on repellent is not always effective as Horse and Deer-flies hunt by sight, not smell.

Although these insects are a painful and possibly harmful nuisance, measures can be taken to avoid them. Pyrethroids and insecticide ear tags or collars have been used on cattle to repel and in some cases kill the insects. For humans, light-colored and long-sleeved clothes can be worn. Wear a hat, and if you want to avoid spraying any insecticides on yourself, a toxic-free and eco-friendly solution is the Dragonfly Wingman attachment. It utilizes the Horse and Deer-fly’s natural predator, the Dragonfly, to ward off those pesky insects. The life-size Dragonfly easily attaches to your hat to keep you bite-free while you grill next to the lake, cast your line into the pond, or to simply enjoy the outdoors.

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