All the CX I have done this year have grown very well. Their average butcher weight has been 4 1/2 pounds at 7 weeks all year........until now. I currently have 2 tractors of birds left. One tractor has 34 birds in it that are 8 weeks old and at best the biggest ones would dress out at 3 pounds. The other has almost 100 that are 6 and 7 weeks old. They look horrible. These birds seemed to be growing according to schedule until the past 2 weeks, then they just seemed to stop. The weather has gotten cooler, but I increased the amount of feed they get per day to compensate, and they have been eating all of it. I have had to postpone butchering the last 2 weeks because the birds weren't ready. I can't figure out what's going on. Here's what I know isn't the problem: It's not the chicks. I sold 50 of them out of the shipment to friend of mine. We butchered them this past weekend and they where huge. It's not coccidiosis. Minimal red colored droppings and no ruffled feathered or lethargic birds. Potential problems I can think of: Some type of sickness/disease - Not sure which one if any. All of them appear to be fine. Eating/drinking ususal amounts, energetic(at least as far as a CX goes). Feed issue - This is the best explanation I can come up with. My mill checked their records and they don't show any errors in the mixing of the batch of feed I'd been feeding, and they have not offered any other possible explanations. I switched to a different feed on Saturday, but so far haven't noticed much growth. Not really enough time to see any noticable growth. Anybody have any thoughts or other possibilities?