# Hatching Eggs the Scientific Way!

Discussion in 'Incubating & Hatching Eggs' started by cchardwick, Sep 16, 2012.

1. ### cchardwickSongster

May 21, 2009
My Coop
OK, I'm a geeky scientist and I have been busy with my new experiments in hatching chicken eggs! I've heard rumors that you can sex the egg before it hatches by how round it is and that the pointy eggs turn into roosters and the round eggs turn into hens. So my first experiment is to test this theory.

The first thing I did was measure the length and width of the egg and calculated a ratio of the two numbers. I used a digital caliper accurate to 0.01mm from my reloading days. I calculated a number by taking the width divided by the length times 100 and rounding to one decimal place. A 'score' of 100 is a perfectly round egg and the lower the number the more pointy the egg. My scores were from about 64 to about 82.

Then I weighed each egg on my kitchen balance accurate to 0.1 gram. I then used a pencil and wrote on the end of the egg with the roundness score on top and the weight in grams below. Then I organized them left to right with the pointy eggs on my left (lower roundness score) and the round eggs on my right (high roundness score).

I then set a weight limit because it seemed that all of my very round eggs were underweight. I chose 45 grams for the weight cut off. Anything below that I considered too light.

I had about four 18 packs of eggs to chose from. These were collected over the last four days since I get about 18 eggs a day. I wanted enough eggs to be able to chose all my eggs from at least half of the eggs on the right, the round ones. I'm assuming a ratio of 50:50 hens to roosters, so keeping with the right half should give me all hens. And keeping with the eggs that weight the most should give me the most healthy chicks.

I'm supposed to get my R-Com 20 Pro with USB incubator in the mail tomorrow and I'm ready to go, I just need to add water and eggs! This will truely test the roundness vs. sex theory!

I dropped and broke one egg while weighing (OH NO!).

I've heard that pencil marks on eggs have no effect on the embryo.

The 20 eggs on the top are the ones I'm going to use, which were selected from the four cartons below. I was three eggs short of filling them all as you can see from the last row on the left, the rooster end.

Tomorrow I can replace this stock photo with the real thing!

Last edited: Sep 16, 2012

2. ### JHorn91180Songster

404
25
123
Mar 20, 2011
Northeast KY
Good experiment but I have tried it b4 myself. Turns out its just a myth. Another way to prove it is by haveing hens seperated by cages and u will notice somthing. Each day u gather ther egg, each hens eggs will look differnt but will almost always b about the same size shape and weight on average. So a hen that lays a round egg will almost always lay a round and and a hen that lays a long egg will almost always lay a long egg as well. If u alternated the same roo in and out of the hens cages each day to make sure all were fertilized by him u will notice about the exact same ratio in pullets and roos per # of eggs hatched from each hen. Shape has nothing to do with sex. Interesting enough chicks from round eggs have a rounder shape and plumpness to them compared to chicks with a longer body structure from long eggs. This usally changes as they grow tho.

3. ### cchardwickSongster

May 21, 2009
My Coop
I've actually heard both sides of the story. I've heard that some people have chickens that will lay all sorts of different shapes, all from the same chicken. And one guy on this site claims he hatched 31 hens with zero roosters this way. I'll either have all hens or a bunch of plump chickens LOL.

4. ### JHorn91180Songster

404
25
123
Mar 20, 2011
Northeast KY
I have had hundreds of chickens and for the most part each hens egg is almost always an exact replica of the egg she laid the day before and the day b4 that ect. Like I sd I have tried this and if u chart the hatches and keep them seperated as they mature u will see it averages about 50/50 in the end. One of my largest roundest UK import roos hatched out of an egg that was almost completely round like a large golf ball. On another note I did notice somthing else interesting. The hens kept back from the round eggs did tend to lay round eggs like thier mothers and the ones from the long eggs laid long eggs also. Not all but more then half in both situations and the rest laid a normal oval egg like most hens do. I would also like a link to the post where the guy states he hatched 31 hens and zero roosters this way. Honestly thats about the same chances of being struck by lightning or winning the lottery. I do agree that hens somtimes lay different shaped eggs but 90 percent or greater will look like exact replicas in size shape and color though out that hens life but tend to gain mass as the hen ages. Seriously tho u dont have to take my word for it but if u knew exactly which of your hens were laying the round eggs and which were laying the long ones u could seperate them in cages by themselves and see they r pretty consistant on egg shape size and color. If u look at the eggs u selected as eggs that will give u all hens and seperated them by size and color. I bet u will notice they seperate in maybe 4 to 6 groups as each group can b linked back to one hen.

Promise Im not trying to spoil your experiment but its just an old wives tale. I will follow your experiment but outta 18 eggs u may at least luck out with more hens then roos from this hatch but if u repeated the experiment several times it will average out. I did this experiment also with hens of one breed and a roo of another to purposely create sexlinks on the first generation so I could sex them by color and know the sex the day they hatched which yeilded yet agian the same results. Good luck and I will follow your experiment. U never know maybe u will have different results and prove me wrong LOL

5. ### cchardwickSongster

May 21, 2009
My Coop
Well I got my incubator today and set my eggs! I had 18 fresh eggs today and five of them met the roundness ratio and minimum weight so I replaced some of the lighter eggs since they were a bit older. The temp and humidity were spot on within an hour or so. I couldn't figure out the software though so the first batch will have to be off the computer until I can figure it out. Here are a few photos, I have about \$5,000 in this setup! I have a huge UPS battery backup that should last a long time even in extended power outages. Retail for that baby is about \$3,000 but I spent less than \$100 for it with shipping included on e-bay! I also have a couple security cameras that I can use to see my chicks remotely once they get near hatching age. The new R-Com 20 has a red display. I have to admit I like the other display better as far as color, but I did notice that they made some improvements to the electronics, one being that you can actually turn off the button noise when turning off the sound function. Here are some pics!

6. ### GittxChirping

113
10
96
Jul 3, 2012
Edom, Texas
I'm anxious to see the results! With my own chickens I have found that if I switch pens for those at the top of the pecking order, and those at the bottom of the pecking order, the hens who went from the top to the bottom began to lay a smaller egg, and those who went from the bottom up, began to lay larger eggs. I'm not sure if it's because at the bottom you get less food and spend lots of time running around to get any at all, and at the top, everything comes easy to you. Hummmm...

7. ### nurse_turtleSongster

3,518
78
201
May 28, 2011
Foothills of NC
100% myth or else we'd all be hatching only round eggs with just 1 or 2 pointy ones.

8. ### JHorn91180Songster

404
25
123
Mar 20, 2011
Northeast KY
Wow Im very impressed and jealous of your bator. Mine are not near that nice or technical. I guess u could say they r very simple compared to that one. Im very interested in seeing your hatch rate as well as I may have to buy a new bator. Eactly how old r the oldest eggs and how many hens to roo ratio do u have? If u already answered these in your post sorry but its late and I have already took my sleeping meds,

9. ### Sally SunshineCattywampus Angel <straightens Halo>Premium MemberProject Manager

56,671
7,933
846
Aug 23, 2012
Pennsylvania
My Coop
I am game! Keep posting!! Curiosity got the cat!!

May 21, 2009