How to tell if an egg will hatch a pullet or a roo...

[grnidone]

OK. I read a thing about a professor in Germany who has figured out a way to determine the sex of a chick when the egg is 6 days old.

http://www.thepoultrysite.com/poultrynews/34741/germany-aims-for-chicken-sexing-in-the-egg-by-2016/

Then, I saw an article that says if you keep your eggs at 40 degrees before you incubate them, you'll get more pullets: http://www.publish.csiro.au/cp/AR9600664

Then, I found this little gem from 1922 that says one can candle the egg and look at the air sac and determine the gender of the chick:
https://archive.org/details/howtotellsexofeg00quis/page/32

My brain is telling me that this article from 1923 is a bunch of crap. Buuuut...then I wonder if there is a grain of truth to it because people worked a lot more with chickens in 1923.

What are your thoughts? Has anyone tried this?

 

[ronott1]

OK. I read a thing about a professor in Germany who has figured out a way to determine the sex of a chick when the egg is 6 days old.

http://www.thepoultrysite.com/poultrynews/34741/germany-aims-for-chicken-sexing-in-the-egg-by-2016/

Then, I saw an article that says if you keep your eggs at 40 degrees before you incubate them, you'll get more pullets: http://www.publish.csiro.au/cp/AR9600664

Then, I found this little gem from 1922 that says one can candle the egg and look at the air sac and determine the gender of the chick:
https://archive.org/details/howtotellsexofeg00quis/page/32

My brain is telling me that this article from 1923 is a bunch of crap. Buuuut...then I wonder if there is a grain of truth to it because people worked a lot more with chickens in 1923.

What are your thoughts? Has anyone tried this?

the only way that I know of is with a sexlinked cross and special candling to see the feathers. I do not if it is used yet but do understand that the chicks are developed enough to have feathers and the goal is to then destroy the eggs with male chicks inside.

the other ways do not work or hatcheries would use them.

 

[WannaBeHillBilly]

I read a bit through the German web-sites about that topic (i am German, so i understand what's written there).
The »laser-guided« chick-sexing method was developer by Dr. Maria-Elisabeth Krautwald-Junghans at the Universität Leipzig since 2008. It is very high-tech, first drilling a tiny hole into the egg-shell with a laser, then using the scattered light of another laser in the near infrared spectrum-range to distinguish between male and female chromosomes, then re-seal the hole in female eggs (they don't describe how this is done).
It seems to be legit and working, but it was developed primarily for the Chicken-Egg industry in Germany (Germans are really squeamish about male chick shredding!). I don't know if this would work for ducks or other birds with wide variations of egg-shell color (that drilling laser must be precisely adjusted). I also doubt that this technology will make it into the hatcheries here in the U.S., as it will increase their expenses and it will definitely be way too expensive for the backyard-poultry keeper for a long time.
Currently the project is in a prototype stage and it is expected to be production-ready for early-adopters within two to three years.

Links to the German web-sites
https://biooekonomie.de/nachrichten/geschlechtercheck-im-ei-auf-dem-weg-die-praxis
https://www.topagrar.com/news/Home-...stimmung-beim-Ei-bald-serienreif-7063978.html
https://www.uni-leipzig.de/service/...chrichten.html?ifab_modus=detail&ifab_id=7689
https://www.tagesschau.de/ausland/kueken-schreddern-agrar-101.html

 

[Mosey2003]

The temperature thing is true, colder temps will kill off male embryos more than females. You can also incubate them slightly cooler. This method would be good if you have a LOT of eggs that will be ready to set at the same time and have the incubator space. You would chill them, set them, and then discard the duds. It's not 100%, but it will skew you towards pullets. The reverse is true also, if you happen to run your incubator too hot, it will kill off more pullets than cockerels.

Out of curiousity, the next time I hatch I will make an effort to track the air cells of the eggs I set and let you know if off-center ones really make a difference. I have a feeling it probably doesn't, but will be pretty easy to track.