The Total Program for Fly Control
Source: Nebraska Cattleman Magazine
By Natalie Jones, Contributing Writer
“it’s imperative that livestock producers provide some means of fly control during fly season,” says David Boxler, a Nebraska Extension livestock entomologist with 40 years of experience with flies and ectoparasites.
“It’s all about increasing productivity and increasing animal welfare – any type of relief you provide them is really important.”
The horn fly, face fly, and stable fly are three fly species that economically impact cattle in Nebraska. With $1 billion in estimated economic losses caused by the horn fly alone in the United States, livestock producers should consider evaluating their management plan, or at least the types of flies impacting their operations and what control methods will work best.
Horn flies, in particular, are considered one of the most detrimental blood-feeding pests of pastured cattle in the United States, with both male and female flies eating more than 30 blood meals per day. With high fly numbers, Boxler says cattle experience annoyance and blood loss, resulting in decreased milk production, reduced weight gain, and changes in grazing patterns and behavior. With an entire life cycle lasting 10 to 20 days, depending on the weather, multiple generations of flies can breed during fly season in Nebraska, which can lead to extremely high populations.
Research at the University of Nebraska-Lincoln’s Gudmundsen Sandhills Laboratory and West Central Research Extension and Education Center has demonstrated that horn flies can reduce calf weaning weights from 4 to 15 percent, and stocker cattle and replacement heifers weights up to 18 percent.
When choosing a fly control program, Boxler emphasizes the importance of producers understanding fly biology, lifecycle, and behavior. Control methods include dust bags, fly rubs and oilers, pour-ons, feed throughs, and insect growth regulators (IGRs), fly parasites, insecticide ear tags, compressed air applications, and traps.
The economic injury level (EIL) for horn flies is 200 flies per animal, a number usually reached by late May or early June. No matter the method, Boxler encourages producers to monitor the effectiveness of their control programs in the mid-morning, when flies are still visible on the topline and sides of livestock. By mid-afternoon, flies will have retreated out of the sun to animals’ underbelly and legs where an accurate evaluation is no longer possible.
Start With Management
What’s the one thing I can do to get rid of flies? That’s a question producers often pose to Michael Hampton, a six-year regional sales manager with Central Life Sciences, who offers rural residents and agricultural operations a line of products to control insect pests. He half-jokingly tells producers to sell all of their cows, because he knows fly control really means a total integrated pest management program, and there is no silver bullet.
“We have to look at everything that’s involved,” Hampton says. “A program really starts not with products, but with management – the things a producer doesn’t have to go out and buy.”
The first two things Hampton says producers need to consider around their farms and ranches are sanitation and elimination of fly habitation. This includes cleaning up feeding areas of old hay, silage piles, spilled feeds, weeds, and anything else consisting of decaying organic material that creates a prime habitat for flies.
For each operation, there will be different fly control methods needed because of location and management style. The same thing doesn’t work for every producer, but there’s always a program and approach that will work.
“Fly control makes a difference to producers – they’re not just a nuisance, they’re an economic loss,” Hampton says. “Whatever producers can do, that money spent on integrated pest management programs, there is a return on that investment.”
Central Life Sciences boasts a brand-new product, EXHALT water dispersible granule (WDG) insect growth regulator, a granular product applied dry or into water as a spray. EXHALT WDG protects livestock by interrupting the pest lifecycle, resulting in a gradual reduction in pest populations, including flies.
Easy on the Cows and Easy on the Cowboys
Once the management side of fly control has been taken care of, one thing is for sure – it’s all about the total fly control program. You don’t just go out and give your animals one vaccination and, poof, they’re all well, says Frank Junfin, founder of The Insectary by Kunafin, a natural parasitic wasp product that controls flies in the pasture and feedlot.
“You do certain things to create an animal health program, just like a fly control program.”
With Kunafin’s program, users regularly disperse parasitic wasp pupae throughout fly season where flies lay eggs in a feedyard or pasture. The harmless, gnat-sized wasps hatch and burrow into the fly pupae, their natural enemy, and lay eggs of their own.
“The most important thing is that it’s all about the program, and the producer must understand that when he is utilizing a good fly management program, not only is he reducing his flies but also helping his cattle,” Junfin says.
No matter if you are utilizing an insecticide ear tag or a fly parasite, it is important for producers to read the entire label and keep safety in mind.
Between tags, sprays, parasitic wasps, and feed-throughs, there are a lot of products that work, but they all have limitations. It truly takes a combination of products and management in order to get an effective, integrated pest management program that works for each individual producer.
“Many common control products used today are upwards of 50 years old,” Boxler says. “For us to move forward and to help better manage these pasture fly problems, we need new control products.”
New fly control management studies are underway. Boxler is currently testing the use of coconut fatty acids and palm oil in an automated spray delivery system. Animals trigger electric eyes and are sprayed on their way to water tanks.
In another University of Nebraska study, the team was successful in using this type of delivery system to reduce stable, horn and face flies. Boxler says many Sandhills producers rely on this type of delivery today and mist the herd as routinely as they check water, mineral, and salt in the pasture.
Editor’s Note: Natalie Jones is a communications specialist for the University of Nebraska-Lincoln. This article reflects the personal views of the author and does not represent an official position of the University of Nebraska-Lincoln.