We raise 50 Cornish Cross Rocks at a time. I've raised them for years and seldom had any issues by maintaining a clean coop and clean water. We start them in a brood box and do not place them outside in their coop until their wings have their feathers. This has always been a measure I use to ensure they are ready for some of our mildly cold upstate New York nights. However, we do not raise any during the extreme cold of winter.
I did experience a learning curve one year when I lost two for no apparent reason and, upon performing an autopsy, found water buildup in the sack around their hearts. I feed mine a blend of soy and corn that carries a higher protein content for these birds and I get it from a local farmer.
They have the opportunity to graze but unlike Red Rangers (or Freedom Rangers) they prefer the feed I give them. Now... here is what happened. I found that if feeding them the high protein feed, you need to take it away from them for 12 hours a day. Otherwise they gorge and the fluid build up occurs around the heart, killing them.
Since we began taking away the feed for 12 hours, we have not lost a single bird. They are a phenomenal bird and look like little Butterball turkeys when processed at 8 weeks. Check us out at
http://www.ourfiveacrehomestead.com
