In the winter raising chickens becomes less of a hobby and more of a job. Depending on where you live it could be better or worse. Where I live we have winters from 20 degrees to 40 degrees. Sometimes their water freezes and I have to break it and fill it up with fresh water. I feed them the same thing year round, but they will eat almost anything. Whenever we eat tomatoes or strawberries we will give them the top part that we don't eat and it is a treat to them. We also feed them stale bread and the love it! This is the first winter that I have had chickens, and I had to read a lot on the internet on what to do. I learned that the worst thing for them is the wind. I put up two tarps on two sides of the coop and some wood on one side.
This picture below was taken on christmas morning.
(Don't know why I was wearing shorts, but I was only outside for a minute :)
I let them out to run around and peck at the ground sometimes and they love being out in the snow. They usually stay under the deck area because of the mud and to stay dry. I have never had a problem with putting them back in their coop because they are usually ready to sleep around 5 or 6 at night. They will all head back to their coop and roost for the night and all I have to do is shut the gate behind them.
I have cats and a dog, but when they are all outside together, they seem to get along. The roosters crow and the hen follows along with the group. Every now and then they all will hear something or see something and get spooked and run away as fast as they can.
After the sun goes down it gets a lot colder. I read that you can use a heat lamp to keep them warm. I used a 100 ft long extension cord and a red bulb heat lamp. I turn it on when it gets colder than 20 degrees. It looks really cool in the dark because the whole coop has a red glow.
In this picture the hen is upstairs and I had just installed the lamp and was testing it during the day.