DE, cayenne pepper,crushed garlic,dieselgrl's poke berries all might be good preventatives, but they wont kill worms. If you want to start a worming program, be prepared to throw eggs in the garbage. A chicken that has worms acts lethargic, doesnt eat or drink much, slows or stops laying and doesnt act like a chicken ie...pecking,scratching etc...I worm according to the weather. If it's hot, humid, rainy all the time, that means the soil is damp and wet which is condusive for worms, I'll worm every 6 months. If it's been hot and no rain for a long time or very cold and no rain I'll hold off on worming and maybe do it every 10-11 months. As you know nuts4chickens, here in Georgia we have dry spells and then at times we need to start building Noah's ark lol. I use wazine17 first, then 2 weeks later I use one of the following wormers: Safeguard, Valbazen or Ivermectin Pour On. The reason for a second worming is because wazine takes care of large roundworms and not their larva nor eggs. Then in 2 weeks use one of the listed wormers to kill them and other types of worms that chickens have also. Worms literally suck the life out of chickens, untreated,it is a slow starvation death for them. When you see a lethargic chicken...that is what is happening,it is slowly dieing. It's the owners fault if left untreated and chemicals must be used to kill the worms, it's too late for non chemicals. Also worms cause damage to the chickens innards. Ready to worm now? Dosage for wazine 17 is 1 ounce per 1 gallon of water for ALL your chickens. Remove all water prior to chickens going to bed at night. Early the next morning put the wazine water out for them. It must be their sole source of drinking water for 24 hours. After the 24 hours is up,discard the wazine water and provide them regular freshwater. On the 3rd day provide your chickens plain yogurt or buttermilk as probiotics to rebuild their immune system, give them extra protein (canned beef catfood) all this mixed in their feed to make a mash,then give it to them. Repeat this for a couple more days. Do not feed their eggs back to them, if you do, you will be extending the withdrawal time beyond 14 days. The eggs may contain wazine in them however slight,all wormers are poisons. Throw the eggs in the garbage. If your still interested in a worming your chickens with the secondary wormers after the wazine, PM me. I'm going to bed. Goodnight.