I read an article that proper feeding of chickens will result in 5 BTU,s of heat in the winter for chickens. I live in Northern Minnesota and it can get very cold. I,m trying to not use an alternate heat source, but rather let them create their own heat. Is crack corn good to use with laying feed to help promote healthy chickens, and will it help theme build body fat? I,m a rookie chicken farmer, got into it because I took my four year old to the fleet store before Easter, now I have 18 chickens.