No, the Demon WP would not have any effect on the eggs produced by the chickens. There is such a small amount that would be in their system that kills them it would be eliminated by the time the chicken would come in contact with the roaches. The chickens would however need to be completely out of the area while you are spraying the Demon WP initially and until the product completly dries.
You can also help by creating a "tick safe zone" in your yard. You should have an area that is at least 9 ft wide between your yard and any wooded area. Trim back trees to allow as much sunlight as possible into your yard. Keep grass as short. Remove as much leaf litter as possible. A clearly defined, well manicured border between your yard and any wooded areas or weedy lots will reduce the chance of ticks infesting your yard.
It is always a good practice to alternate products with different active ingredients. A great alternative to Demon WP would be something like Suspend SC. Suspend SC is a general insecticide that is labeled for various pests, including roaches, mosquitoes, ticks, fleas, etc. This can be used indoors and outdoors around the perimeter of your home. We would recommend 30 days between applications of different products.
Demon WP is not labeled for indoor flea treatments and could cause your lawn to turn white (powdery look). Please let us know if you have already treated with the product or if you were considering this to be a treatment option. The kill time for fleas can vary depending on the life cycle stage. Also, this kill time can vary depending on if and when they came into contact with the product. We will be able to offer advice on application and product suggestions that best fit your needs. It is important to perform a flea treatment indoors and outdoors once every two weeks with a minimum of two applications. Indoor vacuuming will be done daily. Please find our treatment article below that includes helpful videos for flea eradication.
Flea Treatment Article
Demon WP can be mixed 1-2 packets per gallon of water.
Demon WP Insecticide is used for outdoor applications only for flea control. Please take a few moments to review our treatment article on How to Get Rid of Fleas for a successful eradication program.
Demon WP Insecticide specifically states on the product label for Outdoor Flea Control only. It cannot be used inside homes for fleas. When Demon WP is used inside correctly for the listed insects it is only applied to cracks and crevices around rooms, along baseboards and cannot be used across entire floor surfaces where you would need to treat for fleas. Precor IGR would be a great part of treatment along with an insecticide such as Onslaught which can be used on carpets. We also have great guides here for identifying, inspecting and treating fleas to ensure you are correctly treating.