Managing insects in animal production comes with many challenges:
1) large insect populations,
2) limited insecticide choices,
3) insecticide resistance,
4) and the inability to apply most insecticides with animals present, just to name a few. These challenges necessitate an integrated pest management (IPM) approach using multiple control practices to solve our insect problems.
Insect growth regulators (IGRs) are an important part of that IPM program. IGRs control insect infestations at the source of the problem (e.g., manure) rather than treating the symptoms (e.g., adult flies). Two IGR classes are available for animal production: chitin synthesis inhibitors (CSIs) and juvenile hormone (JH) mimics. Both classes prevent immature insects (e.g., larvae and maggots) from becoming adult insects. Here’s how they work.
For an immature insect to grow, it must molt, shedding its external skeleton and producing a new, larger one. Products like Tekko 10 keep newly molted insects from making a new exoskeleton, leading to their death.
Many insects undergo a dramatic metamorphosis (change in form) during their life. For instance, caterpillars transform into butterflies or moths. JH mimics, like Pivot 10, disrupt this transformation, keeping the larvae from becoming an adult insect and breaking the life cycle. After applying Pivot 10, you may still see many larvae in the treated environment. Do not be alarmed! Although Pivot 10 doesn’t kill larvae like Tekko 10 they won’t reach the adult stage and reproduce, preventing future generations. Since IGRs don’t affect adult insects, their benefits will be seen after the second application.
Most users apply IGRs along with a conventional insecticide (e.g., pyrethroid, neonicotinoid, etc.) for faster, improved control. Using combinations provides a 1-2 punch - killing insects up front and preventing immature insects from becoming adults.
As with all insecticides, rotate applications of these two IGR classes to minimize resistance development.
Danny McDonald, Ph.D. Tech Services Manager, Animal Health