Can you post a good picture of the spot you've been cleaning out and removing pus from? Not sure exactly where it is in the pictures above.
I'm going to give you a link to a thread where I explain how I treat very stubborn bumblefoot, and have had success with some really bad ones. It can...
When you've had Marek's confirmed in your flock, then it's always going to be possible. I've found that not all symptoms follow the commonly described ones, there can be lots of variation depending on where exactly it's affecting their systems. Some breeds or genetic lines can be more...
It could be, but without testing or necropsy it's impossible to tell you for sure. Since you have lost several with the same symptoms I would highly recommend that you have one tested, or necropsied when it passes (assuming you have not done that with a bird yet to get confirmation). That is...
If she seems ok then I would just watch. If it gets bigger, or she seems to be having trouble breathing, then I would intervene. Hopefully it will be one that resolves on it's own. If she's eating and drinking and pooping, those are all very good signs.
If her abdomen is swollen, that can be an indication of a reproductive problem. If it's fluid, that's ascites, which is from the liver leaking fluid and can be from various illness's including cancers and infections or organ failure. If it's very firm then it could be from infectious material...
Sour crop usually has a smell, as the contents of the crop are fermenting/spoiling if they aren't passing through. If it's that, then crop issues often have another underlying cause, which can take some time to narrow down. I'm going to give a couple of links, faster than trying to go back and...
More information would be helpful. How old is the hen? Do you know when she last laid? Have you seen her droppings and are they normal, pictures can be helpful? Any wounds or injuries anywhere on her, hiding in feathers? Is she thin, or well muscled, is her keel bone prominent? Does her...
Does it feel like air? Baby chicks can injure air sacs fairly easily by getting banged around, running into things, etc. Sometimes those will heal by themselves. If it gets worse, or the chick is having trouble breathing then the air can be released to relieve the pressure, which will also...
I agree with everything @Wyorp Rock has said. I would clean and apply ointment as she described, and monitor daily for signs of infection. If that happened I would start her on an oral antibiotic like amoxicillin (many times antibiotics are not necessary). I wonder if she may have gotten a...
How old is the bird? Hen? Looks like possible rooster damage from him hanging on when he mounts. If you don't have a roo, then watch for a dominant hen doing it, which sometimes happens when there is no roo in the flock.
It can. If the eggs were on the edge of the pile, they may have gotten cooler. Just about anything can happen when they go from blastoderm to fully formed chick in just 21 days. It's pretty miraculous actually. I've hatched in the heat of summer with high humidity (Florida) and that can have...
Sometimes something as simple as temperature fluctuations and humidity can be enough to affect the developing embryo's. Usually there are more issues with incubator hatched eggs, but even a broody can have issues sometimes, particularly if she's sitting on a lot of eggs and they don't get moved...