I have 2=one year old hens who were rehomed to me a couple of months ago. Both very seem very healthy and were purchased from a feed store by their previous owner. I am planning on getting 2 more chicks from a feed store and am now kind of nervous about potentially introducing salmonella and/or parasites to my existing flock. Should I keep the chicks isolated until they are old enough to be wormed? How concerned have others been about this? Just don't want bring disease into my existing flock but don't want to worry needlessly. Thanks and sorry for all the recent questions.