Hatching chicks, Day 12

The incubator has been humming away, keeping the babies warm as they gradually turn into chicks.  We candled the eggs again today to see what is developing.  According to the experts (eggs-perts?), we should be able to see the heart beat by now.  Unfortunately, due to the color and density of the shells, we've had no such luck.  That being said, we have seen the little chicks wiggling around inside their eggs!

According to the Mississippi State University website, one can expect the chick to grow and develop based on the following schedule:

Before Egg Laying:

Fertilization
Division and growth of living cells
Segregation of cells into groups of special function (tissues)

Between Laying and Incubation

No growth; stage of inactive embryonic life (*my note: an egg can remain undistrubed for up to 10 days before incubation and still be viable.)

 

During Incubation:

First day

16 hours - first sign of resemblance to a chick embryo
18 hours - appearance of alimentary tract
20 hours - appearance of vertebral column
21 hours - beginning of nervous system
22 hours - beginning of head
24 hours - beginning of eye

Second day

25 hours - beginning of heart
35 hours - beginning of ear
42 hours - heart beats

Third day

60 hours - beginning of nose
62 hours - beginning of legs
64 hours - beginning of wings

Fourth day - beginning of tongue
Fifth day - formation of reproductive organs and differentiation of sex
Sixth day - beginning of beak
Eighth day - beginning of feathers
Tenth day - beginning of hardening of beak
Thirteenth day - appearance of scales and claws
Fourteenth day - embryo gets into position suitable for breaking shell
Sixteenth day - scales, claws and beak becoming firm and horny
Seventeenth day - beak turns toward air cell
Nineteenth day - yolk sac begins to enter body cavity
Twentieth day - yolk sac completely drawn into body cavity; embryo occupies practically all the space within the egg except the air cell
Twenty-first day - hatching of chick

So what are we looking at?  By all appearances, five of the eleven eggs have signs of continued development.

Those with veins showing when candled continue to darken more and more each time.  What's more exciting is that some of these now show a pronounced shadow about the size and shape of a large butterbean (about the size of a nickle).  I was surprised this morning when one of these little beans wiggled around as I gently turned it in front of the light.  That 21st day is approaching fast!

What about the others?  About half of the eggs appear to not be developing.  This is not unusual for hens as young as ours.  Most of those that did not grow appear under the candler like the one in the lower right hand corner.  This is perfectly normal.  After the others hatch, we'll start collecting another group and try again.