We've just started buying our chickens scratch now that the weather has gotten cold. I'm wondering how much they really should be getting. I know it's a treat. I bought a 50# bag on 11/8 and our friends needed a new one already this week (we don't have chickens at our house--friends of ours have them and we help with the costs and some of the work). Is that reasonable, or did they give the chickens way too much scratch in a little over a month?