Commercial producers keep birds in as little as 3 birds to a square foot, overcrowding in itself is not the problem here. Being in close contact with other birds does not create a disease but it can create the environmental conditions that cause one.
Environmental conditions causing coccidosis or enteritis, or disease transmission from other birds are the most likely causes at this point. Without identifying what is killing them, you can't effectively treat anything.
Most state's agricultural office will have a dept that does necropsy on dead birds, and it can sometimes be the only way a disease can be properly identified. Many disease only physical indicators are internal lesions that can't be seen unless you view the organ/tract in question under a microscope. At this point you may want to contact the state and get a necropsy so you can be sure it isn't something endemic to your soil.
Any more loss since I checked in last?
Environmental conditions causing coccidosis or enteritis, or disease transmission from other birds are the most likely causes at this point. Without identifying what is killing them, you can't effectively treat anything.
Most state's agricultural office will have a dept that does necropsy on dead birds, and it can sometimes be the only way a disease can be properly identified. Many disease only physical indicators are internal lesions that can't be seen unless you view the organ/tract in question under a microscope. At this point you may want to contact the state and get a necropsy so you can be sure it isn't something endemic to your soil.
Any more loss since I checked in last?