– Neighborly Advice –
Fly Control starts now
Plan to head off damaging effects of these livestock pests
By Todd Steen, ProTrition Ruminant Nutritionist
As the weather starts to get warmer, it’s time to develop a plan to combat flies. From the last frost until the first frost, these pests are prevalent in our area and can certainly be a drain economically on your livestock operation. From increased disease transmission and treatment costs to decreases in production and cow comfort, flies have a damaging effect on livestock. USDA has estimated that cattle producers across the country can lose close to $1 billion annually if flies are not addressed.
For the most part, there are three major species of concern — houseflies, face flies, and horn flies. Of these, the horn fly is by far the costliest. Horn flies are often confused with face flies, but it’s relatively easy to distinguish between the two. Horn flies are small and black, approximately the size of a grain of rice, and spend the majority of their lifecycle on the back, shoulders, and belly of its host, feeding in a head-down position.
Horn fly pupae spend the winter in manure pats, emerging during early spring when average daily temperatures reach 65̊ F for a period of at least two weeks. Having only a 10- to 20-day life cycle, the adult female leaves her host only long enough to lay eggs in warm, fresh manure. Each female can lay up to 500 eggs during her lifespan, allowing populations to increase rapidly. Horn flies begin to have a detrimental effect on cattle at around 200 horn flies per animal. When left uncontrolled, as many as 4,000 per animal may be observed when numbers peak in early summer. Each horn fly takes 20 to 30 blood meals per day by inflicting a piercing bite through the animal’s hide. The ensuing irritation causes cattle to alter their grazing patterns and expend valuable energy attempting to dislodge the flies. This behavior translates into reduced rates of gain in stocker cattle, and decreased milk production and lower calf weaning weights in brood cow operations.
Fortunately, producers have several helpful and efficient options for controlling horn flies to minimize associated losses. Insecticide ear tags, pour-ons, back rubbers treated with insecticides, premise sprays, and feed-through insect growth regulators (IGRs) can all help keep fly numbers in check. The most convenient of these is a specifically formulated cattle mineral supplement containing an IGR. This method eliminates the stress, labor, and expense of handling cattle, while allowing them to spread the horn fly control as they graze.
Feed-through IGRs do not kill adult flies but solely prevent the development of new ones. They are manufactured with a very large molecular size so that they simply pass through the digestive tract of cattle and are never digested so they never enter the bloodstream or meat.
Feed-through IGRs do not kill adult flies but solely prevent the development of new ones. They are manufactured with a very large molecular size so that they simply pass through the digestive tract of cattle and are never digested so they never enter the bloodstream or meat. They are deposited into the manure so that the fly larvae eat the chemicals which prevents the larvae from ever developing into adult flies. For optimum fly control, these products must be consumed daily in adequate quantities such that all manure contains effective levels of the IGR.
In addition to fly control, a complete mineral containing a feed-through insecticide provides additional nutrients necessary for grazing cattle to get the most from pastures. Forages can be deficient in several essential minerals regardless of the season. Phosphorus, copper, zinc, and selenium all play vital roles in growth and reproduction of beef cattle and Co-op Fly Control Minerals help bridge the gap between the animal’s requirements & those provided by the forage.
For the most effective results when using Co-op Fly Control Minerals, begin feeding before flies appear in the spring. Offer mineral in covered feeders and monitor consumption throughout the summer, adjusting placement as needed. When beginning an IGR program mid-season, use an appropriate spray or pour-on to quickly reduce the number of adult flies.
For more information about effective fly management programs, visit with your local Co-op feed specialist.
