by James C. Silverthorne
Now is the right time to modify fly prevention programs with this natural linkage in mind: Manure odors and fly populations are at their highest levels during summer’s warmth. During summer in livestock shelter areas, with even small accumulations of fresh and decaying manure, the odor-fly relationship is causative as manure and urine odors attract some types of flies. Two corollaries to this dynamic include: Fresh air, free of manure odors/volatiles, does not attract flies, and manure not producing odor does not attract flies. Can an ideal manure management/fly prevention program for livestock shelter areas exist in farm practice? The ideal program results in a livestock shelter area (barn, stables, loafing shed) so free of flies, full of fresh air and chemically safe that one could comfortably picnic there with family and friends. Our image of ideal success— the livestock shelter as picnic zone — guides us to its establishment in the real world. What are the most effective foundational materials and methods for the ideal manure odor-fly prevention program, our “castle-in-air” picnic zone?
They are: (1) a cluster of standard low-risk fly-prevention tools to decrease an existing fly population. Several weak items working together can support each other’s actions; (2) an emphasis on decreasing fly attractant levels typical in livestock areas (the volatiles produced by manure, urine, decaying bedding material and spoiled hay/feeds), thereby preventing fly population increase and usually ensuring its decrease. Decreased concentration levels of fly attractant volatiles also make the program easier to accomplish by decreasing the need for the prevention items in (1). Further, with consistently very low levels of manure’s attractant volatiles, area fly traps’ attractant baits become relatively more effective.