Flies in your dairy barn are more than just a nuisance to cows and humans; they can take a bite out of your profits. Negative economic impacts result as flies can reduce milk production when cows expend extra energy fending off flies; cause poor general health; increase vet bills as flies transmit disease from cow to cow; contaminate milk; and reduce worker productivity if they are swarmed when milking and feeding. These winged pests can also delay the entry of replacement heifers into the lactating herd, thus reducing their lifetime milk production performance.

House flies and stable flies are the two fly varieties most associated with dairy buildings. Gone are the days of simply spraying a pesticide and hoping the flies die off. Today, the most successful way to combat unwanted fly populations is through integrated pest management (IPM). IPM seeks to maximize the effectiveness of pest control while at the same time minimizing pesticide use and conserving beneficial insects that prey on flies. With IPM one must first identify which pests are the problems, then stay on top of monitoring the results of the IPM program.

Proper Sanitation

A proper sanitation/waste management routine is the cornerstone of any pest management program. Not only is it the most effective way to rid your facility of flies, it's the most economical way. Pesticides cannot be expected to eradicate flies when sanitation efforts are poor. On average, the fly life cycle lasts anywhere from 10 to 21 days. If you clean your barn on a weekly basis, you can break the fly life cycle. Each week you should remove or spread fly breeding materials including manure, spilled silage, moist hay, wet grain, etc. Areas to focus on cleaning include calf hutches, holding pens, loafing sheds, paths to milking parlors and stalls.

Milk Room

It is vital to maintain a fly free zone in your milk room. Use extreme caution when applying pesticides in milk rooms to avoid illegal residues in milk. If you must use pesticides, check with your milk inspector prior to usage and make sure to cover or remove milk and associated implements prior to spraying.

Non-chemical fly control methods are generally preferred. Installation of tightly closed screen doors and windows leading to the milk room can significantly reduce the number of flies able to enter the area. Sticky tapes and light traps can be used to catch those flies that are able to sneak in through the screening.

Cow Fly Control

After you create a fly free zone in your milk room, the next area to focus on is your cows' environment. You want to make sure flies aren't pestering your cows or breeding in their manure. Below are some different fly control methods to consider:

• Insecticide Ear Tags - These tags release small amount of insecticide that gets distributed over the cow during grooming and rubbing. Prior to tagging your herd, make sure the tags can be used on lactating cows.
• Dustbags and Backrubbers - When placed in "forced use" situations, such as entering and exiting the milking parlor, dustbags and backrubbers provide excellent fly control when treated with various insecticides.
• Fly Predators - Fly predators are tiny non-stinging wasps that are part of a total farm fly control program. Release in fly hot spots around your barn and let the predators start laying their eggs in the larvae and pupae of flies.
• Insect Growth Regulator - When fed to your entire herd, feed through supplements containing insect growth regulators can help control fly populations.

Early & Often

The key to controlling flies in your dairy barn is to begin fly control preparation in early spring before temperatures start to rise and fly breeding season begins. The earlier you act, the less likely you are to have a large fly population. Likewise, a consistent sanitation program will allow you to prevent a large number of flies from invading your facility. Need some help developing a comprehensive fly control program for your dairy? Visit your local Southern States store today.