Courtesy of bovinevetonline.com
As I mentioned in the previous post here, an effective strategy to control flies is necessary for a grazing plan. Horn flies are a very damaging pest for beef cattle here in Texas. Research has shown that a calf infested with more than 200 flies will weigh 15 to 20lbs less at weaning. In order to suppress them in the best way you should understand their life cycle and possible control strategies.
Identifying the fly
Horn flies look very similar to stable flies so in order to identify them you should observe their feeding behavior. Horn flies feed most often on the animal’s back shoulders, and sides. Stable flies tend to feed primarily on the cow’s legs. The horn fly will lay it’s eggs in fresh manure and the eggs reach maturity within 10 to 20 days.
Horn flies usually are first observed in early spring and tend to peak in early summer. This decline is due to the hot and dry temperatures in late summer. The cooler temperatures in the fall generally causes an increase in numbers again till later in the year. When the first good frost shows up they will go dormant till the spring warm-up.
There are many resources available to learn about the horn fly such like from your local veterinarian or your local extension office. Another source of information you can go to is the Livestock Veterinary Entomology department at Texas A&M University
Fly Control Methods
In order to suppress the horn fly population effectively you should use what is called an integrated pest management (IPM) approach. An IPM relies on multiple tactics in order to control fly populations. These tactics include cultural, biological, and chemical methods in order to suppress these pests.
Ear Tags impregnated with an insecticide is a very common product type that many producers use. This are popular because once they are applied to the cow they continue working for months at an end.
Sprayers and dusters are another option that can be used. These products though tend to not suppress flies for very long.
Feed additives are another popular approach for fly control. Some tend to go with this option because it is less labor intensive. You just put the feed or mineral out and that is it.
With each product there is it’s own set of pros and cons that go with them. It is best to visit with your veterinarian to see with options would work for you. Then weigh the options and go with the product that works best for you.
