We're raising our first batch of meat birds this year. 55 birds in a 10 x 12 tractor on prime pasture, moved daily. They aren't cornish x, they're another meat variety (http://www.freyshatchery.com/index1.html the ones called 'heaviest alternative to white rock'). These are just for our family, although next year we intend to raise up several hundred for sale, of both these and white rock (cornish x). So we're trying to learn as much as we can. Our current birds were hatched July 5th, so they are 9.5 weeks now. I had it in my mind for some reason to raise them to 14-16 weeks, but they're starting to look pretty big, and the legs feel meaty. We're also starting to go broke on feed. We're feeding organic feed at $25 a bag and they eat a bag in 3 days. We were looking at another feed that is a few dollars less and it is a 'finisher' not a grower, and has a little less protein. They're on 20% now. I was thinking to do them up next weekend, but my fiancee thinks that holding them on for another month will really see them putting on gains and make it 'worth it'. The cockerels are also starting to fight. Not too badly...but its happening. Nobody has been injured yet. We'll also see freezing temps by the end of the month at night, tho I suppose they'd be ok in the tractor for a light frost. Thoughts????