POULTRYAND
LIVESTOCK
POULTRY
The information and recommendations in this newsletter are applicable to
North Carolina
and may not apply in other areas.
One of the biggest problems I encounter on most farms is the method in which surface-applied insecticides are used to control house flies. There are two mistakes that are usually made: 1) placing the spray where it is not effective; and 2) using the least effective formulation. These mistakes may result in the failure of the treatment to control flies. Inappropriate surface treatments can even make the fly problem worse. There are numerous benefits to correcting these kinds of application mistakes. Application of the correct kind of surface spray to the correct target can reduce labor, reduce the costs applying pesticides, and minimize risks to the environment.
Regarding insecticide formulations, most of us don't think much about the formulation we apply to a surface for fly control. It does make a difference, depending on how porous the treated surface might be. Where surfaces are porous (unpainted cement block and wood for example), a wettable powder formulation is generally the best choice. Once dry, wettable powders leave a more uniform residue on these rough, porous surfaces. Emulsifiable concentrates, on the other hand, are absorbed into porous materials and may not be as well distributed over the surface of porous building materials. Emulsifiable concentrates are equally effective on less porous surfaces such as painted blocks, metal and vinyl. Even though wettable powders are as effective in this case, they may be less desirable because they are harder to mix and require constant agitation.
There is one other point to be made about formulations and the type of surface treated. Remember that no matter which formulation is used, rough, porous surfaces will need significantly more spray for thorough coverage than smooth, impervious surfaces. For example, cyfluthrin formulations used for fly and beetle control call for 1 gallon of spray (water) for each thousand square feet of painted plywood surface. Compare that with the recommendation of 2.7 gallons for a thousand square feet of unpainted plywood. Where painted cement block is to be treated, cyfluthrin labels still call for 3.2 gallons of spray per thousand square feet. Treatment of unpainted cement block calls for 36 gallons of spray for each thousand square feet!
Fly sprays also need to be targeted where they'll do the most good. All too often I see surface sprays for fly control applied to every available surface in poultry houses and other livestock buildings. This practice is wasteful and can be dangerous to non-target organisms. Surface sprays in broiler breeder or layer houses, for example, are most successful when treatments aimed at adult flies are kept away from the manure under slats or cages. Indiscriminate treatment of slats and other surfaces where spray drift and runoff covers large areas of manure surface with insecticide should be avoided. Failure to do so makes it certain that the parasites and predators that destroy fly eggs, larvae and pupae will also be killed. A more selective approach to the application of fly sprays significantly reduces this risk and saves both labor and insecticide.
The house fly is the biggest pest around most animal operations,
and fortunately, they exhibit a behavior that makes it a relatively
simple task to apply surface sprays for control. House flies tend
to migrate upward at night. A large percentage will spend the
evening resting on rafters and other overhead surfaces. That is
the place to direct surface sprays. It is not necessary to spray
the entire building from top to bottom, and inside and out.
Similarly, treatment under eaves and on the southern or eastern
exposures of exterior walls will often yield good results.
Southern and eastern-facing walls are particularly good treatment
areas when evening temperatures are cool. Large numbers of flies
gravitate to these exposures to warm themselves in the morning.
After a number of years, a new single-dose active ingredient for rodenticides is available. The common name of the chemical is difethialone and it is marketed under several brand names (Hombre, Dcease and Just One Bite II Mouse Bait). What seems promising for this rodenticide active ingredient is that data indicate that it's more effective against mice than other single-dose active ingredients. Difethialone baits are typically formulated at 25 parts per million; half that of similar rodenticides. According to laboratory trials, this active ingredient is also effective at doses about 1/3 smaller than similar active ingredients.
One other item about rodenticides and rodent control needs to be
mentioned. Remember to follow label directions. Unintentional (or
intentional) poisonings of non-target animals can result in fines
and prosecution under federal and state pesticide laws. Be sure
that children, livestock, poultry, and pets do not get the
opportunity to eat any of the rodenticide. Restrict access to
baited areas and use bait stations where appropriate.
Web page last updated on 29 July 1996 by Stephen J. Toth, Jr..
