This may be a dumb question, but I have four 11 month old chickens of various breeds. I've raised them from day-old last february and so far they are as healthy as can be. They do free range around my yard and are kept impeccably clean. I clean all their droppings every morning and change out the run every other week. I change their water every other day and clean out their feeders between feedings (Once every two weeks). They also get a sprinkling of DE in the nesting boxes, in the sand in the run, and over their food when I clean the coop. That would be every other week or so. I believe they had their initial vaccinations as hatchlings, they had some medicated and some non-medicated chick feed back in the day. Now they just eat layer pellets and kitchen veggie scraps and drink plain clean water. They also forage around our property which is a large normal urban landscaped backyard. My question is, how do I keep them this healthy? Should I worm them this spring as a preventative? Should I be doing anything else to maintain the level of healthiness they already have? Sunnier times! *note the chicken wire has since been replaced with hardware cloth thanks to reading BYC posts!