Shoe Stable Fly!
Swatting at flies is a major aggravation but luckily for us, we can often shoe away these annoying arthropods before that painful bite. But what about cows and other livestock that only have a tail to defend themselves?
Besides a quick pinch, stable flies actually have a huge effect on cattle costing the U.S. cattle industry more than $2.4 billion! How might you ask? Animals will often stop grazing and bunch together to minimize the number of bites they're getting. Consequently, this can reduce milk production in dairy cows, decrease weight gain in beef cattle, and reduce feed efficiency.
Generally, ranchers will use insecticide sprays to keep these pests off of their livestock. However, as cattle graze through wet grass or wade through water, the spray washes off and the treatment is rendered ineffective.
It also doesn't help ranchers that larval development sites of the stable fly exist for only a short time and are difficult to find.
To combat these issues, scientists at the Agricultural Research Service's Agroecosystem Management Research Unit (AMRU) in Lincoln, Nebraska, are looking at better ways to locate breeding grounds, find more efficient ways to control them, and asses the damage that stable flies cause.
One of the main habitats for stable flies larvae is the large bales of hay placed in the middle of fields which are used for winter feed. "The accumulation of wasted hay, manure, and urine at these feeding sites creates an ideal habitat in the pasture for stable fly larval development," says AMRU entomologist David Taylor. Cleaning up these infested sites has been the main stable fly control method for the past century, however, the hay-feeding sites are often in remote locations.
So instead the team is focusing on using an insect growth regulator to interrupt the development of stable flies can be effective. In one study, Taylor used cyromazine to control immature stable flies. Cyromazine, a commercial product, has been used to control other species of flies, mainly in poultry production. It interferes with molting and inhibits proper development of the insect's external skeleton.
"We wanted to develop a method where the producer could apply a single treatment and be done," Taylor says. Scientists found that a single application of granular cyromazine sprinkled on a hay-feeding site reduced the number of adult stable flies emerging by 97 percent. Treatments took about 10 minutes, cost $10 per site, and remained effective for 10 to 20 weeks.
Read more at USDA Agricultural Research Service.
Cows with flies image via Shutterstock.