Are you in an area prone to migratory birds???
I would be seeking a vets advice quickly to be on the safe side.
try and look at theses as worst case;

http://www.ehow.com/list_6060252_chicken-comb-diseases.html

Title; e-how -
Chicken Comb Diseases | eHow.com

also look at;
http://www.cdc.gov/healthypets/animals/birds.htm

Animals: Birds | CDC Healthy Pets Healthy People

These are worst cases - may be something simple and harmless - STILL - have it checked out - esspecially if in contact with migratory birds!!

Hi,

I am afraid, I can't help in terms of what it is, I have never had anything like that, but if you have the turkey's sick and on antibodics, the first things that come to mind, is you need to split these birds up, the turkeys in one pen with their medication, the healthy birds in a clean pen, with possable preventive antibodics and all sick birds, the second you see them become "off" going to their own cages/small pens.

Given the loss's you appear to be talking about, I do think getting a vet to have look is a good idea so that you have a firm idea of what kind of meds is required, having said that, depending on where you live in canada (I am assuming canada) pretty much all the basic vet care antibodics for chickens are available at the local feed store, so you could buy the basic three, and treat three different "off" birds and see which med works, therefor having a way to treat the sick birds that will work.

Personally, I would call in the vet if you can do so (I have lived places that this would not be possable, so I know that is not always as easy as folks say), but getting a firm idea of what is causing it is ideally the best thing, but the hard truth is, finding the meds that will help is point in fact more important.

I will point out a note, if the birds that recover go to butcher and have internal damage, it is possable that they will still not pass bucthering time, I have had friends that have treated for different things only to not get the birds back when sent in.. it can happen.

On a side note, how often are you cleaning their dish's, and pen/bedding while dealing with sick birds, and what are you using to disinfect them with?

I'm wondering if someone can help me with my chickens, they've been ill and I'm not sure whats wrong. They're in a pen with some turkeys who are being treated for mycoplasmosis with some antibiotics. The chickens are heavy meat type, and are ready for slaughter now, except we can't while they've been having the antibiotics. They seem to not want to get up much, and the combs and wattles of the sick ones are dark dark red, versus the bright red of the healthy ones. It seems to be slightly more with roosters. They are sick for a day or two and then they die. Does anyone know what this might be?

Did you ever discover what was wrong with your flock? I'd be interested in knowing.

Along with the fact the chickens should never have had access to the antibiotics, what probably happened was the meaties hearts simply couldn't do the job any longer. They should have been sent to meet their maker sooner. It is very common for this to happen. Nothing to be done but butcher them before they kick the bucket. Do a quick autopsy to make sure the organs look normal and chow down.

Turns out its because they're the heavy commercial breeds (an unintentional purchase). The legs and hearts give out when they get to full size. We butchered the remaining few out of pity, but they didn't look very appetizing and became dog food. The hearts were really misshapen, and the blood was off colour. Definitely will be more selective next time, hoping to get some good heritage breeds. Turkeys are fine at least.