Louisiana researcher gives cattle some relief from stable fly attacks

After a trip to Zimbabwe 12 years ago, Louisiana State University livestock entomologist Lane Foil brought back a novel idea for stable fly control. All it involved was a piece of cloth, drenched with insecticide, placed in an area where the flies reside. Flies would land on the cloth, be exposed to the insecticide, and die.

Stable flies prey on large warm-blooded animals, including humans. After their meal, female flies lay eggs in areas like large hay bales mixed with urine and fecal material. Flies typically feed at least once a day, and on an average day, cattle can have as many of 50 sets of new flies attacking their legs. In response to the attacks, cattle “bunch” together and stop grazing.

Stable flies cost Southern cattle producers approximately $500 million each year. Aside from insecticidal sprays on the legs of the animal, no control measures have been proven effective for stable flies. Because the flies do not live on the animal, the leg sprays are only moderately effective. Foil used funding from a Southern Regional IPM grant in 2010 to test an integrated control strategy for stable flies.

Credit: Billy Hathorn

Credit: Billy Hathorn

Foil used an electric grid study to compare the attraction of stable flies to either a blue, black or blue-black cloth treated with permethrin. He also used the grid to determine if the height of the cloth made a difference in the number of flies caught. One cloth was placed one meter above the ground; the other was placed on the ground.

The grid study revealed that there were no differences in the number of stable flies of any of the colored cloths. In addition, although the cloths alone can kill between 3,000 and 4,000 flies per day, the electric grids kill more than 4 times that number. Results suggested that cattle owners should use whatever colored cloth was easier and less expensive, placed close to the cattle at ground level.

Researchers found that the cattle’s stress reaction to infestations of stomping their front legs was reduced by over 50 percent when 6 treated cloths were placed around 5-acre areas. When implemented, the integrated cloth target / electric grid treatment results in a weight gain of about 50 pounds over a 100 day period.

The Southern IPM Center is made possible by the USDA NIFA Crop Protection and Pest Management Regional Coordination program under agreement 2014-70006-22485.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: