I have two older hens and a rooster with my year old hens and they just seem shabby and old to me....and I worry about putting stress on them. They are missing lots of feathers and they just are a little banged up and slow. It's not like a big problem but I'm looking for tips on what should be looking out for to keep them healthy. They are between 3 and 4 and I don't think the hens are laying. Any supplements or special food. Should they be treated for parasites or should I be looking out for any deceases. What about care in winter. I worry the roosters big comb will get frostbite. They get layer organic food and some scratch. Curshed grannet and occasionally a little cat food for protean. What about giving them any kind of oil, vitamin, protean, supplement....I hope this isn't a silly question but I want to take good care of them. Thanks!