Did my chicken freeze to death?

Last night it was about 18 degrees here in central New Hampshire. My 10 hens have been in the coop for several days - the coop is in the barn, rubber mats over wood on the floors, and pine shavings over the rubber mats. They have plenty of food, and water that's on a defroster (heated tin)

Anyway, we went out this morning and one of my buff orpingtons was dead on the ground inside the coop! It clearly didn't fall off the perch and break its neck - it was off away from the perch.

These hens are 6 months old. They are eating layer pellets, and get scratch too, as well as other treats like grapes and a supplemental kibble.

any thoughts? I've read from so many people that the chickens will be fine in cold temps - but what else could have happened last night?

thanks in advance

other info: we were getting 5-8 eggs daily (not all of the hens had started laying yet), including one hen that appears to be laying rubbery eggs that break on a daily basis.

Very unlikely he froze to death my chickens even my silkies see much colder temps most everyday now and im yet to lose one to cold in over 25 years. Id look for other signs any other symptoms as of late? Was it acting differently is there anything different looking about it? I really very much doubt it was the cold.

I didn't notice any odd behavior other than this:

I think a lot of my chickens would do this, but this one in particular: they got into this stage in the past few weeks where if you approached them, like opening the door of the coop when they were in the way, for example, instead of moving away they would kinda dig their feet in: they'd squat and spread their wings a little bit like they were taking a stand! I thought it had something to do with the fact that they were all starting to lay.

other than that, no odd behavior.

as for the body: the eyes were glossed/clouded over - I thought that was probably just because they (the eyes, that is) were "wet" and it was freezing out...

the dead body was twisted a bit - in a position that I've seen the chickens sleep in sometimes when they're basking in the sun.

I would look for other things.
A healthy chicken won't freeze to death at 18 degrees.
Could be something she ate.
How is the air in their housing. Can you smell ammonia?
Something to remember is that sometimes they die from no apparent cause and without a necropsy there's no telling.

Quote:
That is the desire to breed and doesn't necessarily relate to egg laying. Hens that are with a rooster rarely do this.
Hens usually do this for their owner if there's no roo whether the owner is man or woman.

I doubt she froze to death. Sounds like you are doing a nice job caring for them. Is the coop area in the barn pretty draft-free?

What is "supplemental kibble", though?

Also, I switched to layer crumbles because my chickens did not care for the pellets. I suppose if they had a lot of the other food you described available free choice and continually chose it instead of the layer pellets, that might cause a problem (but it seems to me more like a long-term problem, not a "keeling over at six months" problem). Maybe someone with more food expertise than me will check in here.

It is most likely just one of those things that happens and you won't know exactly why.

Edited: cuz i caint spel.

ChickenCanoe -

let me see if I can describe the coop for you: it's built into the barn, so three walls of the coop are "interior" and one is exterior - the outside wall of the barn. On one of the interior walls, there are two windows - about 5 1/2 feet off the ground. They are covered with screen - not glass. I mention this because we have 1 1/2 of the two interior windows covered over with plastic sheeting for the winter to reduce drafts. There is still 1/2 window (the windows are probably 18 inches high x 3 ft long) open for airflow.

As for ammonia: I can smell ammonia slightly - not overpowering. I cleaned the shavings last week, but now that the hens are not getting out during the day (we have a predator problem too - got one 3 weeks ago), they mess it up much quicker.

Damselfish: the supplemental kibble is a nutrient rich kibble that I mix in on a very small ratio with the layer crumble - 1 to 10 ratio. It's just a little supplement, and I doubt it would have anything to do with it. The bag says something like "bringing free range nutrition to the coop"

I don't want to mischaracterize their food options: the hens eat mostly layer crumble. They get grapes a few days a week, and scratch every day now that it's cold.

Was this particular hen laying, or could you tell? It's possible that her death came from some laying abnormality, like internal laying.

It sounds like they're getting good nutrition.
I had bought feed the twice in the last year that had gotten moldy and returned it.

I mention the ventilation thing because chickens have tiny respiratory systems and are very susceptible to bad air issues.
I know lots of people warn about drafts but I know chickens that sleep in trees. How do they stay out of drafts?

I don't sweat the drafty thing opting for maximum ventilation. I know most people don't have this much but I've read and recommend 1 sq. ft. per bird.
I originally built coops with big windows on east or south side but my newest coops have half walls open on opposing sides and no health problems. I'd take the plastic off the windows.
Cold doesn't kill chickens but bad air does.

@Elmo - I can't tell if this chicken was laying.

@ChickenCanoe - thanks for the advice - I'll discuss it with the wife: she wants to turn the heat lamp on because she thinks they're too cold...

coop size: my coops is about 14ft x 14ft. we started with 12 birds and are now down to 9 (2 predators outside, then this mysterious death).