When it comes to the type of chickens that are raised for their eggs as opposed to their meat, the hens are obviously more valued than the non-laying males. As a result, when the chicks are being sorted at hatcheries, most of the cockerels (male chicks) are culled either through asphyxiation or by being thrown into a grinder. Needless to say, this practise is troubling to many people. It may soon no longer be necessary, however, thanks to an inexpensive new technique that determines the gender of developing embryos while they're still in the egg.
The technology was developed by a team led by Roberta Galli of TU Dresden (Germany) and Gerald Steiner of TU Dresden and Vilnius University (Lithuania).
It involves shining a near-infrared laser through the shell of an egg, four days after it's been laid. This causes the embryonic blood within to fluoresce. By analyzing the manner in which it fluoresces, it's possible to determine whether the embryo will become a hen or a cockerel.
When tested on 380 eggs, the new technique proved to be 93 percent accurate.
"In ovo sexing based on spectral analysis is non-invasive, does not require extraction of egg material and does not use consumables," says Galli. "Moreover, the method is applicable during the fourth day of incubation, before onset of embryo sensitivity at day seven, and is therefore in agreement with animal welfare."