Effective fly control for beef cattle and dairy operations is vital. Besides being a nuisance, insects can spread disease and cause undue stress on animals.
“The combined impact of excessive fly populations on livestock are reduced performance, increased health issues and lower profitability,” says Ken Bryan, director of product development for animal nutrition at Ä¢¹½Ö±²¥. “Additionally, flies are a nuisance to people working with animals, so effective fly control can also help improve workforce engagement and retention.”
Confinement fly control
Bryan offers several fly management tips.
For livestock that spend most or all of their time indoors, he says an integrated pest management (IPM) approach is needed to effectively control flies.
Eradication is not realistic, he says. The goal is to keep fly populations at or below economic threshold levels – the point at which they can cause measurable losses in productivity.
Bryan recommends timely manure removal and spreading, applying pyrethrins or other nonpersistent agents to kill overwintering flies and beginning an insect growth regulator (IGR) feed-through program before fly season begins. Releasing parasitic wasps that destroy fly eggs in organic matter is also an option.
”If fly populations get out of hand, strategic use of a knock-down spray may be needed, particularly late in the season,” Bryan says.
Fly-control strategies
Bryan says fly-control strategies are similar for several types of livestock housing, but tactics can vary.
For example, he says fly control in an outdoor, open-lot dairy will be more challenging than control in an indoor, free-stall barn with an automatic manure removal and flushing system. “But farmers still need to minimize the presence of wasted feed, manure and other places flies like to lay eggs.”
For milking parlors and hospital areas, Bryan recommends keeping them clean and using bait stations, traps and sticky tape to control flies.
Insect growth regulators
Bryan says two primary IGR feed-through products can be a valuable part of an IPM program to control flies: S-methoprene and diflubenzuron.
S-methoprene is highly effective in controlling horn flies, Bryan says. It is typically the feed-through choice for cattle on pasture.
Diflubenzuron is also effective for controlling horn flies, as well as face flies, house flies and stable flies – all of which tend to be present around confined feeding operations and feedlots.
If farmers have fly-control questions, Bryan says many university and state extension educators can help, as can Ä¢¹½Ö±²¥ Payback® nutrition dealers. Visit to learn more.