I have lost multiple chickens after they consumed insects killed by a commercial insecticide used around my lab. The applicator stated the insecticide is safe around animals that are not arthropods. It kills chickens, songbirds, snakes, lizards, frogs and toads very quickly. The applicator I make certain applies the insecticide only in certain areas.
Chickens exposed to the stuff through both ingestion and contact through feet get into trouble quickly, and in three instances I know it occurred the birds were dead by heat of day (exposure early in morning) or dead by dawn when exposed later in the day. They got slow, lay down, and died. The applicator claimed different materials used each time and neither cause issues.