By carrying out a sound fly-control plan, producers can keep their cattle happy and healthy. Producers, in turn, will be rewarded economically. (Photo by Robert Waggener)

Cattleman’s punctuation lesson of the day. Is it:

Dos and don’ts?

Do’s and don’ts?

or

Do’s and don’t’s?

Some would argue that all three are correct depending on which grammar guide is sitting on your desk.

But one thing is certain. If you’re a beef cattle producer and ignore either the dos or the don’ts when it comes to managing horn flies and face flies, those nasty little buggers will do both you and your cattle a great disfavor.

“I have worked with horn flies for more than 30 years, mostly testing different control products, and know the damage that these flies can cause,” says Dr. Nancy Hinkle, a professor of veterinary entomology at the University of Georgia.

She says horn flies can torment cattle unmercifully and also cause bad outbreaks of summer mastitis, which can torment the pocketbooks of producers.

Hinkle says that ear tags can be used effectively to control both horn and face flies through much of the season, especially if they are used in combination with feed-throughs that eliminate horn fly larvae.

When using ear tags, Hinkle urges producers to keep the issue of insecticide resistance at the forefront of decision-making.

“Every product we have tested works really well initially, and because they are so successful, producers tend to use them several years in a row,” Hinkle notes. “And when they do, insecticide resistance can develop rapidly.”

That’swhy people like Hinkle and Dr. Doug Ross recommend developing a multi-year plan that includes rotating classes of insecticides every year.

“The biggest mistake I see with ear tags is not rotating correctly,” says Ross, senior technical services entomologist with Bayer Animal Health.

Ross says that there are currently three classes of insecticides on the market for horn and face fly control: pyrethroids, organophosphates and abamectin.

“In order to best manage resistance in horn flies—one of the most economically important pests of cattle—it’s important to rotate the three different modes of action year to year,” he says.

And this is where diligence comes into play, and part of that diligence depends heavily on reading labels.

“Proper rotation is more than just changing tag companies, brand names or active ingredients each year,” he emphasizes. “You need to use an active ingredient from a different class with a different mode of action than the one you used the year before. When you rotate to another active ingredient, you need to be sure it doesn’t belong to the same class as the last one you used.”

There is no bible when it comes to winning the horn-fly battle, but Ross offers the following suggestion:

“This recommendation came out a few years back, and it’s probably still one of the best ones out there,” he says. “Use a non-pyrethroid two years in a row, and then a pyrethroid for one year.”

And during the two off years, there are two options, so it’s advisable to use an organophosphate one of those years and abamectin the other, Ross adds.