Egg with Strange Inclusion

[Poppy Putentake]

A few days ago, I found a small abnormal egg in a nesting box. It was a bit less than an inch in diameter and soft-shelled. (The "shell" was a thin membrane.)

Inside, there was some albumin (but no yolk), surounding a grayish object about the size and shape of an almond or slightly bigger. Cut in half (See photo.) it appeared to consist of a tough, leathery, somewhat wrinkled, "skin" (upper right) and a clear inside that looked like albumin but was blood-red (lower left).

All except one of my hens have been laying normally before and after I found this. The other hen is a Specked Sussex about one year old that had been laying at a steady rate of 4 or 5 eggs per week since age 7 months, but has not laid any eggs for the several days since that abnormal egg appeared. She has always been active and healthy-appearing, and still shows signs of still being in an egg-laying state (squatting, appearance of vent). However a few weeks ago, that hen's eggs changed in appearance from brown and smooth to very pale and rough on the surface, with a noticablly darker and rougher area towards the larger end. In the 2nd photo (of one of these eggs), you can a clear boundary between the rest of the egg and the dark area on the large end covering about 1/4 of the total surface.

I am worried that this may be a sign of something unhealthy going on in the hen's oviduct, but it is unlike anything I have heard about before.

 

[aart]

Inside, there was some albumin (but no yolk), surounding a grayish object about the size and shape of an almond or slightly bigger. Cut in half (See photo.) it appeared to consist of a tough, leathery, somewhat wrinkled, "skin" (upper right) and a clear inside that looked like albumin but was blood-red (lower left).

Probably a piece of tissue, likely an immature ova released.
Only time will tell if it's a serious health issue or a glitch.
Fairy, fart, wind, rooster eggs are usually from a tiny piece of tissue breaking loose from the reproductive tract, or an immature ova(yolk) and the body forms an egg around it. Color can be darker than 'normal' as the pigment coating released has to cover a much smaller area so is thicker. Can happen with any age layer, but more common with older layers.

However a few weeks ago, that hen's eggs changed in appearance from brown and smooth to very pale and rough on the surface, with a noticablly darker and rougher area towards the larger end.

This is not too unusual either.
How old, in month, is this bird?

 

[Poppy Putentake]

The hen is almost a year old, from hatchery May of last year. Always healthy and active, no problems, although always slightly on the small side. (Weighed just 31 grams when I got her.) Laying steadilly since mid December last year until now. The hen has been sitting in a nesting box for a while for 5 days now but without laying an egg.
Other minor problems with my flock have been soft-shell eggs from an Australorp (from 2018, so now 6 years old) last spring and this spring, which resolved last year after about a month after giving that hen vitamin D (in pellets of corn meal mush containing about 1/25 the human daily dose (1,000 IU).) Had the same problem for a short time this year too, and also supplemented with Vitamin D, but by putting it in wetted chicken feed offered to all the hens (so the Sussex got some also).
My hens also had lice this spring and last, which I treated with permethrin powder applied to the feathers around the vent, treatment repeated after 7 and 14 days.

 

[Poppy Putentake]

Just discovered two eggs with the same size. shape, and color as the ones the Sussex had been laying before, but not in nests, on the floor of the coop. Both had very thin, almost paper-like shells -- just a thin layer of calcium over the membrane. So that's why I haven't been seeing any eggs form that hen recently.
The Australorp's thin-shell egg problem had resolved completely and her eggs are now nicely smooth and light brown, but at the same time, the Sussex went from normal eggs, to pale, rough ones, to these very thin-shelled ones.
What are the cause and the remedy? Will recently delousing the birds make a difference? Should I give them more Vitamin D or other supplements?
I'm also concerned that this may lead to some of the hens getting the egg-eating habit, if they are often finding broken eggs on the coop floor. I found the first thin shelled egg because one of the hens was eating it.

 

[Poppy Putentake]

Update: This morning the hen laid a basically normal egg, although similar to what she had been producing lately -- pale, with a slightly darker rough area at the large end. At least a step in the right direction.