It’s a beautiful spring day but, rather than enjoying the fresh new grass, your cows are all swishing their tails and stamping their feet.
Because they’re surrounded by flies.
Not only are flies annoying, but a heavy infestation can also cause all manner of unpleasant side-effects for your bovine buddies.
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Biting flies not only affect your cows’ behavior but can also lead to weight loss and low milk production.
Face flies, for instance, “carry the bacteria that cause pink eye, Moraxella Bovis” that can quickly spread throughout the herd, requiring expensive treatment.
Commercial cattle farmers usually opt for chemical fly repellants and feed supplements to deal with any fly infestations, but, by and large, homesteaders prefer a more environmentally-friendly approach.
Come, fly with me, and together we’ll identify the types of fly we want to deter and what is the best way to keep flies off cattle + the fly control options are available.
Which Cattle Flies Cause the Most Distress?
All flies are annoying, but some “are considered to be significant pests of both free-ranging and confined cattle.”
These are primarily blood-feeders like the horn fly, face flies, as well as deer and horse flies.
The horn fly‘s Latin name, Haematobia irritans couldn’t be more fitting. It roughly translates as “blood irritant” and indicates how the horn fly uses its “piercing/sucking mouthparts” to deliver a painful bite to a cow to take its required 20 to 30 blood meals a day.
At the height of the fly season, there may be hundreds of horn flies on each adult animal, collecting around their horns, and congregating along their backs and sides.
These “biting flies are a serious concern for livestock owners because they affect cattle’s behavior and can lead to economic losses.” (source)
Deer and horse flies also inflict very painful bites, causing significant blood loss and negatively affecting weight gain.
Face flies don’t hurt cows with painful bites, but the females “use their rasping, sponging mouthparts to stimulate tear flow from the animal’s eyes and noses,” (source) and then feed on cattle secretions, such as blood, nasal discharge, and saliva.
In doing so, they also transfer eye infections, wound viruses, and even dysentery from animal to animal.
What Is the Best Fly Control Program for Cattle?
“File:CSIRO ScienceImage 1887 A Closeup of the Buffalo Fly Trap.jpg” by division, CSIRO is licensed under CC BY 3.0
Controlling your fly population will generally involve regular spraying of cattle, especially during the heavy fly season.
You also need to consider how you manage your manure piles as these are breeding grounds for all types of fly.
The type of food you feed can also affect the fly population, so persistent fly control may require certain supplements, as well as external fly repellants.
Using Insecticides for Optimum Control
If you’re comfortable using chemicals on your cows and your land, the following solutions can reduce the number of flies per animal and protect your livestock cattle herd from irritation, infection, and disease:
1. Types of Feed and Larvicide Supplements
Some feeds contain an insect growth regulator or larvicide, such as Altosid, which prevents horn flies from breeding in your cows’ manure, making it an effective form of horn fly control.
Alternatively, you could add a larvicide supplement to your cattle feed which will have the same effect.
2. How to Use Insecticide Fly Tags
Ear tags can help reduce heavy populations of the horn fly, and combat attacks from face and deer flies. While they’re not usually recommended for lactating dairy cows, they’re safe to use pastured cows.
Ear tags are most effective once you have 200 or more flies per animal, using them any earlier than this may decrease efficacy.
3. Pour-On Horn Fly Insecticide
Safer than an ear tag, pour-on insecticides can be used on lactating cows, as well as providing effective fly control in calves.
Most pour-on products are effective against horn and face flies, as well as biting and sucking lice.
The Best Natural Control Solutions to Keep Flies Off Cattle
Not everyone wants to use chemicals on their cows, and nor do they have to.
Admittedly, during a particularly heavy fly season, you may not have much choice, but often natural fly solutions can be just as effective, or even more so, than their chemical counterparts.
Animals sprays are one of the easiest ways to control horn flies and other pests, and making them is pretty simple too.
How to Make Your Own Fly Repellant For Cows
Citronella Essential Oil from Starwest Botanicals Inc.
- 1 cup apple cider vinegar (where to buy apple cider vinegar)
- 1 cup mineral oil (where to buy mineral oil)
- 2 tablespoons dishwashing soap
- ½ teaspoon of the following essential oils: lemongrass, bitter orange, and citronella (where to buy these essential oils)
- ¼ teaspoon eucalyptus oil and clove essential oil. (where to buy these essential oils)
Mix all the ingredients together in a glass storage jar. (Makerplace has an awesome range of high-quality mason jars, perfect for this purpose)
- In a spray bottle (you can use plastic or glass spray bottles, which are amber-colored to preserve the potency of your essential oils), combine your fly repellant concentrate with water on a 1:5 ratio.
- Shake well both before and during use.
- Apply all over the cow every day or, with heavy infestations, twice daily.
How a Walk-Through Fly Trap Works
“File:CSIRO Science Image 1929 The Buffalo Fly Trap.jpg” by division, CSIRO is licensed under CC BY 3.0
The walk-through horn fly trap was designed by entomologist Willis Bruce almost 100 years ago and remains just as effective today.
The cattle enter at one end and walk through the 10-foot trap, making contact with a series of canvas or carpet strips as they go. “These strips dislodge most of the horn flies on the animals’ backs and sides” so “the animal exits the trap with fewer flies on it, and the trapped flies cannot escape.”
Not just clever, but completely eco-friendly to boot!
Some Alternative Natural Cattle Flies Remedies
1. Bring In The Predators
Introducing or encouraging natural fly predators to live and breed on your farm can help control fly populations, especially amongst pastured cattle which may be more difficult to spray or treat than confinement cattle.
Ducks and chickens “do a great job of catching and eating flies in their paths,” or you could introduce beneficial bugs like fly predators which are very small, non-stinging wasps that lay eggs in the fly pupae and feed on the larvae.
2. Go With Garlic
In addition to using your homemade fly spray, you could add a little garlic powder to your cow’s feed.
Canadian researchers found that “cows fed trace mineral salt fortified with garlic powder had 52% and 56% fewer flies on average than the two control groups fed plain trace mineral salt.” (Source)
3. Zebra Crossings
If none of the options listed above strike you as the best way to keep flies off your cows, then you could try painting your cow to look like a zebra. I know, it sounds silly, but it’s actually very effective if a little time-consuming!
A study performed by Japanese scientists in 2019 revealed that painting zebra-like stripes on a cow could reduce the number of flies per animal by over 50%. “The scientists believe the striped pattern confuses the fly’s motion detection and deters the pests.” (Source)
What’s Your Best Way to Keep Flies Off Cattle?
While insecticides and chemical repellants are used widely to keep flies off cattle by commercial livestock farmers, they’re not always the best option for small-scale farmers and homesteaders, many of whom have a more holistic approach to farming.
Although insecticide ear tags, pour-on fly repellants, and larvicide supplements are all effective at controlling fly populations, more natural approaches can produce similarly positive results.
The best way to keep flies off cattle is, in my opinion, to make them all zebra-striped pajamas but, realistically, a more sensible approach maybe just to add garlic to their feed and concoct a homemade animal spray.
At the end of the day, the choice is all yours.