2 hens have died??? Any ideas

[Corgihome]

I'm hoping someone can help, we've had our first winter with our flock about a month ago we had one hen die. Didn't think much about it she was a small 9month old hamburg who would refuse to come off the roost when it was cold. Which was basically for the past 4 months as we've had -10 degrees and colder multiple times this winter. But yesterday I went out to chore and our delaware hen 10 months old was lethargic and weak. I tried feeding her, etc and it wasn't really that cold in the 30's in the coop. She died while I was at work today. All the chickens I have had mareks vaccinations. Everyone else looks ok for now, but I don't want to loose anymore and I had plans to add new chickens to our flock this weekend.
As an FYI the new chickens were hatched by me and we haven't shared anything between the two groups yet.
Thank you for your help!

 

[chooks4life]

Was the one that died first emaciated? Refusing to stop roosting when it was cold sounds like she was likely starved. Starvation can occur even when they're eating regularly, so the best way to find out is to check them on the perch at night, feeling their keels. You can detect problems long before the bird's behavior starts showing something's wrong. If they possibly can they will act normal right up until they are dying. Causes of starvation can include internal blockage, parasite overload, disease, poisoning, and tumors.

There are often diseases present in the soil, some of which can live for decades in dormancy; also wild birds can carry diseases to your poultry. Almost no ground is truly pristine.

Personally, I would use hydrated agricultural lime on the grounds, everywhere they walk, worm the birds, start feeding them freshly minced/crushed raw garlic every day for a week and after that at least every second day, and put apple cider vinegar (unfiltered, unpasteurized, with "the mother") in their water, as all these things attack different parasites and pathogens before they get out of hand, and sometimes even take care of the problems after they've gotten out of hand. I would autopsy all the dead birds if possible, or send them somewhere they will be checked for cause of death.

You may prefer to try other methods but whatever you do, best wishes with it.

 

[Corgihome]

Was the one that died first emaciated? Refusing to stop roosting when it was cold sounds like she was likely starved. Starvation can occur even when they're eating regularly, so the best way to find out is to check them on the perch at night, feeling their keels. You can detect problems long before the bird's behavior starts showing something's wrong. If they possibly can they will act normal right up until they are dying. Causes of starvation can include internal blockage, parasite overload, disease, poisoning, and tumors.

There are often diseases present in the soil, some of which can live for decades in dormancy; also wild birds can carry diseases to your poultry. Almost no ground is truly pristine.

Personally, I would use hydrated agricultural lime on the grounds, everywhere they walk, worm the birds, start feeding them freshly minced/crushed raw garlic every day for a week and after that at least every second day, and put apple cider vinegar (unfiltered, unpasteurized, with "the mother") in their water, as all these things attack different parasites and pathogens before they get out of hand, and sometimes even take care of the problems after they've gotten out of hand. I would autopsy all the dead birds if possible, or send them somewhere they will be checked for cause of death. 

You may prefer to try other methods but whatever you do, best wishes with it.

I did check them both for obstructions, didnt see anything weird. Thank you for the suggestions. I'll give it all a try.