3 days ago I got 14 chickens around 1 1/2 yrs old. They looked and acted fine except I did notice they were overweight. On the ride home I started smelling an odor similar to a wet dog smell. They did smell like mangy mutts like they had been cooped up with dogs. I also noticed something a little odd, they looked like they were yawning alot. Several of them would open their beaks and slightly hold their head in an upward motion and looked similar to a yawn. I have them in a separate room of the chicken house away from my other chickens. I filled the water jug up and they gobbled down the water like they hadnt seeen water in a long time. I filled it twice. They also gobbled down a bucket of food like savages. I went down the next morning and there was something wrong with one of them. She was very lethargic and I happened to look at one side of the wall and looked like there was vomit on it. I also noticed balck tar like poop that did not smell like regular chicken poop would smell like. I picked her up and on the way up to the house she vomited a couple more times. It was tanish like liquid. I have never smelled a dead corpse before but I can almost bet that that is what it smelled like. It smelled so bad! She died this morning. What could be going on here???? This morning I walked down to the chicken house to check on everything. The new chickens seemed fine although I have not given any food today, only water. Yesterday I gave them plain yogurt. Anyway I noticed one of my regular chickens that I've had for the last couple of years now doing that same yawning thing. I know they have never did that. I'm always with my chickens everyday.
Welcome to BYC. Just guessing on the one that died is that she may have had sour crop that cause those symptoms. You may want to refrigerate her body in a plastic bag and send it in to your state vet for a necropsy. That way they can check for other things to find a cause of death.
Do the chickens have any nasal or eye drainage, bubbles in eyes, swelling of the faces, sneezing or noisy breathing? The neck movements can be a sign of adjusting their crops, but sometimes can indicate a crop problem or even a respiratory issue. You must keep these chickens quarantined away from your other chickens for 30-45 days to make sure they are healthy or you could infect your whole flock.
I would worm them with Valbazen 1/2 ml orally to each chicken and repeated in 10 days, check them for signs of lice or mites on their skin all over and near their vents. If Valbazen can't be located, then use fenbandazole (SafeGuard, Panacur.) Permethrin spray or garden dust can be used to treat lice and mites.
In the mornings before they eat, check their crops for a few days to make sure that they are emptying overnight. It sounds like they were not cared for very well, so I would give them vitamins and probiotics in their water to build them up. Watch for diarrhea or hens standing around hunched or puffed up--that might be a sign of coccidiosis which can be common when they have been kept in dirty conditions or move to new ground.
Here is a link for your state vet to ask about a necropsy, and another good link about common diseases and symptoms:
I have already buried the chicken that died, but if any others die I will send one off to be tested for sure. After I posted I started to research on the symptom, that only I can describe as yawning or fake looking crows without the sound, and read about that particular behavior as a sign of gape-worm. I'm almost positive that is what it was. I treated them with Ivermectin by putting a little bit on the back of their necks on the skin. That symptom has stopped immediately. None are no longer doing that anymore. I sit down there for an hour watching. Their poo is looking like normal poo after feeding them that bowl full of plain yogurt. I just noticed one that had still pooed a brown colored poo, not a whole lot, and it wasnt diarrhea looking like it had been or the color of back tar. Kind of looked like a brown cottage cheese but not as runny like it had been. And that had just came from one chicken, the rest are pooping fine. Their waddles are pale looking and look chapped. My other chickens wattles are bright red or close to it. I started giving them electrolytes in their water today. There is a couple that have a slight puffiness to them and I did notice a couple standing off by themselves puffed up like as you described. There is no sneezing, or runny noses, or watery eyes like you described though. All those parts look pretty normal except for the pale chapped wattles. While spending time with my other chickens I already had, I am noticing they are shaking their heads every so often. I'm thinking a mite infestation?