Originally Posted by BuckeyeChickens
90% of the commercially grown chickens for MEAT are the Cornish/Rock or Cornish Hybrid....they are bred to produce lots of meat in the shortest time (usually about 8 weeks). In a commercial environment they would do as "TinyHouse" says....die from heart failure or their legs will break from their body weight. however, lots of folks successfully raise these same birds on pasture and supplemental feed without the problems "TinyHouse" suggested, yet most of them are butchered somewhere between 8-12 weeks of age anyway! Unless a chicken is labeled otherwise it will be these Cornish/Rocks....even those "organic" chickens can still be these Hybrids just fed an "organic" diet!!!
Not doubting you (because I don't really have that much experience with them) but how do they raise them to an age they can actually lay eggs? I spent time on a farm last year where we did pasture Cornish/Rock crosses and they mostly just laid around until the feed showed up and then they acted like they hadn't eaten for days!
They got to the point where they could barely walk. I can't imagine how we'd have been able to have kept any of them alive past the 8-week mark where we butchered them. We had some turning blue and dying and when we cut them open, their hearts were enlarged, flabby and surrounded by fat.
And as you pointed out, there's a difference between "organic" and "heirloom". A chicken can be a hybrid and still be raised organically. Heirloom and organic would be the ultimate bird.