Behavior problems other than dominant birds pushing others from food wont show up in the time frame of life for meat birds. Males and dominant females will push others away from food. There needs to be plenty of space around food troughs.
Dual purpose are just as tender as meat birds. The difference is you let them grow out longer so they get more texture and flavor with age. The older the bird that texture becomes tough if not cooked properly. Expired layers or old cock birds will only be good if stewed or crock pot cooked to use the meat. Soup, dumplings, enchaladas, chicken salad, gumbo and chicken pot pie are the way of old birds. If stewing don't let the water boil or you'll toughen the meat. Low heat and long cooking time to aid in breaking down of muscle tissue.
Meat birds are just that, a hybrid bird that's purpose in life is to eat and grow. They get so big so fast they are the most tender bird people eat excepting a cornish game which is a CornishX butchered at around 4 weeks of age. It's rather incredible to have a 4 lbs dressed bird in 6 to 7 weeks. They have the least flavor of any chicken due to being so young. They have thee most white meat to dark meat ratio too. Double thick breasts. It takes rationing of food to have CronishX grow to adult age. Not all are successful but people do raise females for breading to make project birds. Rare for projects like this to succeed. Outcome is not up to standards or people miss the incredible meat conversion and quick growth of CornishX hybrid.
Dual purpose grow much slower. You can eat any and all chicken but the dual purpose can have fair size in 12 to 14 weeks. If butchered by 14 weeks they can be broiled or grilled. Meat birds are called broilers as they are young enough to broil and never live long enough to not be able to cook that way. With dual purpose the least able cooking method is what they are called. A broiler can be cooked by any mens you want. 14 weeks to maybe 20 weeks are fryers (? not sure how old still able to fry). Over that age is roasters and most feel year old birds are stew though I've still roasted year old breeding cock prospects and they were fine if brinned and cooked at 325F. You'd not want to roast much over that age for sure. Old birds are stew birds. The only method of cooking that can be done. Crock pots work of course.
Edited by Egghead_Jr - 4/11/16 at 2:50pm