I'm building my first chicken tractor. I figure it will be ready in about a month. I have an idea of what breeds I like based on pretty colors, egg laying frequency, egg color, and local availability. I figure popular local breeds will do well in my climate. I plan to start out with 4 chicks. I'm looking at Wyandottes, Barred Rocks, Ameraucanas, and maybe a Speckled Sussex. I want variety, but it'd be nice to get them all together from the same place. We'll see. I live near Dallas, TX, so a month from now, I'd expect the daily temps to range between 70- 85 in the day to 50-60 at night. I have a large dog crate that will be suitable for 4 chicks as a brooder. Obviously, they will need food and water, but I have a few questions. 1. What do they eat? I've heard of oyster shells in their food and scratch mix, but what do you start a week old chick on? 2. At what age can I let them graze secured in the bottom of their tractor run? I want my 4 dogs to be introduced to them at a very young age and seeing them grow up may help them become used to chickens. I wouldn't mind letting them graze during the warmth of the day and bring them in at night before it cools off. 3. At what age will they be more robust and be able to handle cooler temps and move into their coop permanently? We rarely see any freezes until after Thanksgiving. I figure they will be about 6-8 weeks old by then. Thanks in advance for the advice.