Hi everyone! Really hoping we can get some answers or ideas on here! This problem is getting VERY frustrating. Basic problem: Cornish Cross broiler chicks seem healthy until about 3 weeks old, then they randomly start dying. We start noticing chicks that seem to be constipated, i.e. they are straining to poop, but can only get whitish liquid out, their abdomen seems swollen and hard, they stop eating, they die. Background - We have been raising several batches of 100 Cornish Cross broilers per year for the last 5 years. It is mainly the business of my younger brother, although in the last 3 years I have helped a lot with managing and feeding, especially when they are small. We feed a homemade Soy-Free, Organic feed using non-toxic beans and Fishmeal as protein, and Organic Corn, Wheat, and Oats for bulk & energy. I research the protein content of each grain and try and formulate it to recommended protein/fat levels for broilers. We also use Fertrell's Poultry Nutribalancer supplement and Thorvin Kelp in the feed for added nutrients & probiotics. In the last two years we started soaking/fermenting the feed as well, to increase absorption and digestion. We also put ACV in the drinking water for the chicks. Environment - We raise the broiler chicks in a large brooder in one side of our garage. It is basically an 8ft x 16ft box with plywood walls about 2ft high. It is divided in the middle into two 8ft square boxes and we put 50 chicks on each side. The brooder is directly on the cement garage floor, and we use several inches of pine shavings as bedding. Depending on time of year/temperature, we hang 1-2 heat lamps per side over the center of the brooders for warmth, although this year we just started experimenting with the Premier1 Large Heat Plate brooders, with varied success. For the first week or two we make a circle in the brooders with flexible pieces of vinyl siding, to prevent the small chicks from crowding in the corners. We usually have two of the 20 inch red chick feeders on each side, and two chick waterers. We grind our homemade feed finely for the small chicks,and give them chick grit, and also try and give them chunks of sod or dirt to scratch in as soon as possible to boost their immune systems and give other options for grit. History of problem - The "Three Week Old Epidemic" started last year in Spring of 2013 with our first batch of Cornish chicks for the year. The previous fall (2012) was the first time we had tried the fermented feed with the broiler chicks, and we had great results, with nearly 100% of the chicks making it until processing day! So we were eager to continue with the fermented feed. The 100+ chicks the hatchery sent seemed to do GREAT the first three weeks, and were noticeably large and healthy for their age, compared to previous batches. Two days after they turned 3 weeks old, we found a dead chick in the morning, and saw a couple others that were having trouble walking. By evening we had lost 6 chicks in one day! Before the chicks turned 4 weeks old (three days later) we had lost 10 more chicks to the mysterious problem! We tried adding garlic & oregano to their feed to boost immune systems. Some of the chicks would seem to get partially paralyzed or have cramped muscles right before they died, with one leg or wing stuck partially out and they would be screaming and trying to move. Then we started to notice the constipation trend. We tried giving them prune juice, electrolytes, etc. It seemed to help a little with some, but not enough. We called MSU poultry specialists, but they didn't seem to have a clue what it was. We went over our feed formula again and again, trying to think what could be different, or wrong. Were the oats giving the chicks too much fiber? What was the problem? We moved the remaining 85 chicks out to our hoop houses on pasture, where they would be moved to fresh grass daily for the remaining 4 weeks of their lives. This seemed to slow, if not stop the deaths, and the remaining chicks stayed healthy until processing. The confusing thing is that since then we have had a similar problem, though to varying degrees, with every batch of chicks since then! After the first few initial expected deaths, from weak chicks from the hatchery, the rest would do fine until right around 3 weeks old, when we would start noticing the constipation problem, and start finding dead chicks - large otherwise healthy chicks - almost every day until we moved them out to the hoop houses! We have tried everything we can think of - giving them lots of fresh pieces of sod and grass in the brooders, this year we bought totally new, clean pieces of plywood in case there were some bacteria or virus in the old plywood sides of the brooder. We removed Oats from the feed thinking that was the problem, but this last batch did the very same thing - never having eaten an oat at all! We are over thinking everything - do we need to add fresh bedding more often to the brooder? We have been trying to get them out earlier when possible, in their 3rd week, instead of waiting until after they are 4 weeks old. The problem does seem to slowly stop after they get out on pasture, but we just can't get them out there soon enough! Please! If anyone has any idea what this could be or what we can do to stop it, I would love to hear your suggestions! If you need any more information on how we are feeding or caring for the chicks, please ask. I know this post is way too long already!