Egg

[Turtle]

Originally Posted by CraigD

...An egg come out of the hen rather soft and flexible, until it’s air-dried a while. Were they aware of the alternative of the shell hardening while still inside, I’m sure hens everywhere would be grateful for this characteristic. ...

Originally Posted by Freezner

...Something that has not been addressed yet is the shape of an egg. As Craig mentioned, the egg is soft when fresh out of the chicken. ...

You two Gentlemen share the same (apparently common) misinformation on the condition of a chicken's egg on laying. To whit, they are already hard-shelled when laid. >>

Originally Posted by uiuc.edu

25. Is the shell hard or soft when laid?

The egg is hard when laid by the hen.

Here's that bit and a lot eggstra. >> Incubation and Embryology - Incubation and Embryology - University of Illinois Extension

[freeztar]

Originally Posted by Turtle

You two Gentlemen share the same (apparently common) misinformation on the condition of a chicken's egg on laying. To whit, they are already hard-shelled when laid. >>

I don't think so Turtle.

Most bird eggs have an oval shape, with one end rounded and the other more pointy. This shape results from the egg being forced through the oviduct. Muscles contract the oviduct behind the egg, pushing it forward. The egg's wall is still shapeable, and the pointy end develops at the back side.

Egg (biology) - Wikipedia, the free encyclopedia

Is a chicken's egg soft and elongated soon after being laid,...

Perhaps "soft" is the wrong word. How about malleable?

[CraigD]

Originally Posted by Turtle

You two Gentlemen share the same (apparently common) misinformation on the condition of a chicken's egg on laying. To whit, they are already hard-shelled when laid. >>

Here's that bit and a lot eggstra. >> Incubation and Embryology - Incubation and Embryology - University of Illinois Extension

Originally Posted by freeztar

I don't think so Turtle.

Egg (biology) - Wikipedia, the free encyclopedia

Is a chicken's egg soft and elongated soon after being laid,...

Perhaps "soft" is the wrong word. How about malleable?

I’m disposed to believe the University of Illinois page over the answerbag.com one, which is IMHO about as authoritative as my post here at hypography.

I’ve lived a total of perhaps 2 weeks in households with hens, most recently in 2002, but must confess I believed their eggs were flexible when laid because everyone told me so, not from direct testing – I never handled an egg when it was dark and wet, only after it had dried to its usual white color. My impression was that even then, I could slightly (~ .001 m) compress them, but my perception may have been due to suggestion – I didn’t use calipers or any other objectively sound technique, just thumb and fingers.

Does anybody have a hen?

[InfiniteNow]

The issue is you are all searching for an absolute answer to a dynamic question. There are many factors which influence the malleability or rigidity of a freshly laid egg (one of the main ones is what type of animal is laying it). However, you have referenced hens specifically, so basically diet, gestation time, and age all seem to be the predominant factors. Also, it's important to remember that each egg has nearly 10,000 microscopic pores, so our classic definitions of hard and soft don't really allow us to resolve the issue very successfully.

Cheers.

The outer coating of the shell itself consists of a mucous coating called the cuticle or bloom which is deposited on the shell just prior to lay.This protein like covering helps protect the interior contents of the egg from bacteria penetration through the shell.
<...>
The thickness of an egg shell is determined by the amount of time it spends in the shell gland (uterus) and the rate of calcium deposition during egg shell formation. If the egg spends a short period of time in the shell gland, then shell thickness will be less. Also, the time of day when the egg is laid will also determine the thickness of the shell. In general, the earlier in the day or light portion of the photoperiod the thicker the shell will be. The amount or rate of calcium deposition will also affect the thickness of the shell. Some strains of birds may be able to deposit calcium for the egg shell at a faster rate than others. Another factor such as the age of the hen plays a role in determining the functional quality of the egg shell. As the hen ages, the thickness of the shell usually declines. Other egg shell quality factors such as the formation of abnormal ridges, calcium deposits, or body checks (ridges) are important considerations in determining egg shell quality.
<...>
Although it may not be practiced, the use of a "ahemeral" lighting program has shown to be effective in causing eggs to spend a longer time in the uterus, thus, producing eggs with thicker shells. Nutritionally speaking, it is important for the producer to feed a ration properly formulated with the correct amount of calcium and phosphorus in the diet (usually 3.5-3.75% calcium, .45% phosphorus). The production of eggs with thick, strong shells usually occurs from young vs. older flocks. Thus, a producer should expect more shell breakage and eggs produced with thinner shells to occur with older flocks and those producing eggs a couple of months after they’ve been molted. It is also important for the producer to monitor the health of the flock. Since diseases such as Infectious Bronchitis and Newcastle cause egg shell abnormalities in the texture of the shell and shape of the shell, producers should continually monitor their flock for these diseases and follow management practices to avoid their flock from contacting these diseases.

What is Egg Shell Quality and How to Preserve It

[Turtle]

Originally Posted by CraigD

I’m disposed to believe the University of Illinois page over the answerbag.com one, which is IMHO about as authoritative as my post here at hypography.
...
Does anybody have a hen?

Hear hear. Let uncommon common sense prevail. I have in mind to call some egg farmers tomorrow.

On the thickness of the shell business, it is only tangentially connected as thickness of a material does not equate to its hardness. The thicknes may affect how much force is necessary to break a material, but not how the material breaks.

Moreover, "hardness" may not be the best term as what we are really getting at is how an egg cracks and a measure of "brittleness" is better applied. >> Brittleness - Wikipedia, the free encyclopedia

I assert that an egg fresh out of a hen's cloaca is already brittle and will crack on the skilllet edge every bit the same as an older egg.

[Buffy]

Completely orthogonal idea from this month's Popular Science mag which has a wild set of articles on "high-tech cooking!":

Ever drop a tiny piece of eggshell in your eggs and tried to fish it out? Next time use *another piece of eggshell* to dig it out! Apparently it cuts right through the gooey plasma-stuff, instead of what your finger or spoon or anything else which just pushes it away....

Apparently those eggshell edges are *really sharp* when you get down to that cellular level....

What if Humpty Dumpty had been newly laid,
Buffy

[freeztar]

Originally Posted by Turtle

I assert that an egg fresh out of a hen's cloaca is already brittle and will crack on the skilllet edge every bit the same as an older egg.

Although this wiki on oviducts is absent of much info, the picture says a thousand words. The egg shape is apparent in the uterus, which suggests that the form is already hardened. Otherwise, we would expect to see the egg in a shape formed by the natural volume and shape of the oviduct.

So thanks Turtle, for correcting me.
Perhaps, if we can find a good source, the wiki for "Egg (Biology)" can be changed. No sense in perpetuating a false myth...

[Ganoderma]

slightly off topic, but the title is Egg not bird eggs...

when i was breeding reptiles i noticed, especially in lizards, that the amount of calcium intake (and therefor the amount used in egg production) directly related to shell hardness. some animals that had very little calcium (especially those that have already laid a lot of eggs in a season) would lay eggs that are sometimes almost opaque ad quite soft. then theres the ones that are laying for their first time in the year, for example, and are stuffed full of calcium sometimes had eggs so hard the babies had a hard time breaking it. also i found Vitamin D3 and sun exposure had some differences but i never really looked into it that much, but that is directly related to calcium.

but reptile eggs are far different from birds eggs many times. most reptiles rely on an egg tooth to break the eggs, usually meaning softer eggs while birds got them big honkers to bust through with.