What has longer longevity among hens? (RIR"s, Red Sex link, Barred Plymouth Rock's?) Also I have hens that are 11 months old, I haven't wormed them, they are laying everyday...they haven't free ranged in over a month due to snow cover. Do I have to use a preventative of something to keep them healthy? what is a good disinfectant for the chicken coop ? I heard white vinegar in a spray bottle works??