About Fly Eggs

When you own a horse, pony or donkey, you also declare war against flies and fly eggs. Many species of flies are not only annoying to horses and their grooms, but also spread disease and internal parasites that can get a horse very sick. Taking preventive care by daily grooming and taking care of the manure pile will also cut down on flies and their potential to harm your animals.

  1. Types

    • There are three main types of fly eggs to worry about. The first and most common type are flies that lay their eggs in manure. Types of flies that do this include stable flies, house flies, black flies and horn flies. The manure acts as food for the developing maggot. The second type are bot fly eggs, which are laid directly onto the host animal's legs. The animal licks them off, swallows them and the larvae develop inside of the horse's digestive organs, causing great internal damage. The third type are flies who lay their eggs into water for them to develop into flies that bite horses. These include deer flies and horse flies.

    Prevention/Solution

    • Fly eggs that live in manure need the moisture in the manure in order to develop. By breaking up the manure and spreading it in the sun, the fly eggs are exposed and dry out. Bot eggs need to be taken off your animal's legs with a bot knife. Areas of standing, stagnant water need to be removed to cut down on places where horse or deer flies can lay their eggs.

    Warning

    • Although working to eradicate fly eggs is important in stable management, sometimes this won't be enough to get rid of flies. You need to keep worming your horse regularly to kill off any internal parasites the flies can transmit through their bites or their eggs. You will also need to use fly repellents to keep away adult flies from your animals.

    Bot Fly Eggs

    • Female bot flies look like tiny bees without mouths. They can lay 100 to 300 eggs in their short life of a few weeks. The eggs are laid in summer to early autumn. The bot fly eggs look like little orange or tan specks that will not come off your horse's legs by means of regular brushing. The warmth of a horse licking his legs stimulates the eggs to hatch into larvae. You can use warm water to make the sticky eggs hatch and then remove the larvae, but usually you need to use a razor, bot knife or bot scraper to remove the eggs. The eggs must be disposed of or they may somehow get accidentally swallowed by your horse (see Resources below).

    Potential

    • Another stable management technique for combating flies is to release fly predators in the stable area. These predators lay their eggs in the fly eggs inside of manure. There isn't a fly predator for bot flies, though (see Resources below).