Why am I getting these misshapen eggs consistently?

[Weeg]

Does anyone know why I keep getting these eggs from my Mallard hen Pinecone? I'm fairly certain its her because of how blue it is. Could be Rose's egg, she's a Mallard cross. Her eggs are usually larger and lighter blue.
I've been getting this misshapen eggs consistently for about 5 days now. Its really weird. It was soft shelled today, the shell cracked just by grabbing it. I'm going to blame that on running out of Os for about a week.
I looked through this article and read about causes for misshapen eggs-
https://www.backyardchickens.com/articles/common-egg-quality-problems.65923/

Causes-

- Immature shell gland (young layers); She's not a young layer, and this is the first time I've noticed this problem.
- Defective shell glands; ? I don't think so. She's never had this issue before, unless this can just pop up out of no where?
- Disease such as infectious bronchitis; ? I'm not seeing any symptoms for it as far as I can tell. Sunny, an older hen of mind has always had a bubbly eye, but I think thats a lingering eye infection which I need to get back on board for treating. But honestly, following Junies death its definitely concerning.
- Stress, frights, or disturbances; Seems unlikely? The drakes and separated, and the hens get along fine. Maybe theres predators lurking at night? I'll have to turn on the security camera to check. Otherwise everything is completely normal.
- Overcrowding in the coop and/or run. The "coop" is an 8x8 outdoor dog run/kennel. Plenty of space for 7 hens. I only have 6 in there since Junie passed, but I say 7 since it started before Junie's passing.

Any ideas? Is it something I should be concerned about? Honestly, following Junies death its definitely a concern.
Photos of egg in comments.

 

[Weeg]

Photo of misshapen egg-

They all look just like this, same shape. I've been getting them consistently from the same hen for about 5 days now. Every egg she lays looks like this.

 

[Weeg]

- Stress, frights, or disturbances; Seems unlikely? The drakes and separated, and the hens get along fine. Maybe theres predators lurking at night? I'll have to turn on the security camera to check. Otherwise everything is completely normal.

Speculating at this point, but it seems like if this was the cause more birds would be affected and showings signs of stress? Last time this happened, the entire flock dropped egg production for about a week. It seems odd that it would only be one duck if stress was the cause?

 

[3KillerBs]

I'm far from an expert in diseases and health problems, but it seems most likely that if a single hen is suddenly producing odd eggs unlike her norm that aren't a one-off glitch then some kind of illness or physical malfunction seems likely.

 

[Weeg]

I'm far from an expert in diseases and health problems, but it seems most likely that if a single hen is suddenly producing odd eggs unlike her norm that aren't a one-off glitch then some kind of illness or physical malfunction seems likely.

Darn it. This makes me really regret not doing a necropsy on Junie.
Its also odd to me that I just lost my Mallard hen, and now my other Mallard hen is laying odd eggs.
I'm going to tag some experts, and see if I can find a vet who can do testing on my birds.

@Isaac 0 @Miss Lydia

I think that @KaleIAm also has first hand experience with infectious bronchitis. Shoots, this on top of ALV, when does it end.

Also going to tag @Chicken poppy and @MGG so they can follow along.

 

[Weeg]

Now that I really think about it, I have noticed head shaking in my poultry before. Since I never saw any other symptoms, I always blamed it on the rain, or the ducks shaking their heads after swimming.

 

[Weeg]

Going to add @Wyorp Rock and @azygous as well since I know chickens can get it too. Maybe they have some thoughts on it in general.

 

[Chicken poppy]

Darn it. This makes me really regret not doing a necropsy on Junie.
Its also odd to me that I just lost my Mallard hen, and now my other Mallard hen is laying odd eggs.
I'm going to tag some experts, and see if I can find a vet who can do testing on my birds.

@Isaac 0 @Miss Lydia

I think that @KaleIAm also has first hand experience with infectious bronchitis. Shoots, this on top of ALV, when does it end.

Also going to tag @Chicken poppy and @MGG so they can follow along.

Thanks for the tag. Im so sorry to hear that

 

[azygous]

Do you see any additional symptoms in the hen that is laying these odd eggs? Head shaking is one symptom of respiratory illness. Any odd sounds when she breathes? Any swelling around the eyes? Look into her throat and ears for any crusty stuff.

 

[Weeg]

Do you see any additional symptoms in the hen that is laying these odd eggs? Head shaking is one symptom of respiratory illness. Any odd sounds when she breathes? Any swelling around the eyes? Look into her throat and ears for any crusty stuff.

The ducks are pretty afraid of me, and because of that I don’t I spend enough time with the, close enough to notice many consistent symptoms like head shaking. I haven’t seen any swelling, but can get a closer look when I get home. I’ll check her breathing too. I haven’t noticed anything like that so far.
I’ll check for crusty material as well.