Non-invasive and cost-efficient

CHEGGY is ready for practical use

The animal welfare-friendly alternative to the practice of culling day-old male chicks is in ovo sex determination with CHEGGY. This fully automated machine uses hyperspectral imaging technology that identifies the gender in the brown layer lines by embryonic plumage colours. Technology that is currently used for sex determination does so in the second-third of the incubation period.

CHEGGY is able to safely check up to 20,000 eggs per hour. Thanks to its non-invasive process, there is no risk of contamination and no risk of injuries to the embryo.

Sustainabale and climate friendly

Contribution to climate protection

CHEGGY not only offers the advantage of making an important contribution to animal welfare, but is also sustainable. One factor contributing to this is the accuracy of the machine: Over 96 percent of hatched chicks are female. In addition, in ovo sexing saves resources. Furthermore, the process does not require any chemicals.

The Hyperspectral Measurement Technology: Process Overview

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The hyperspectral measurement technology

Let there be light

Due to gender-specific plumage colours in brown layer lines, the sex can already be determined in the embryo based on its first feathers. This is how it works: inside the measuring chamber, eggs are illuminated from below and a spectral image is taken from above. The spectrum of the image is then analyzed by a computer automatically. By using an algorithm, that, in contrast to neural network, is based on a so-called parametric model, the sex can be determined.

The procedure is non-invasive, keeping the eggshell intact. Based on differences in the measured light spectra, an algorithm classifies the gender. In addition to sex determination, unfertilized eggs are also identified and sorted out at the same time.

The hyperspectral measurement technology does not require expensive consumables. This is another reason why it is around one-third of the cost of alternative methods and, most importantly, is more environmentally friendly.

Study results

Results of a large-scale field study in France

hatched female chicks 38 %
sexing error 4.1 %
hatching eggs per female chick 2.6
hatching eggs per female chick (standard) 2.4
extra demand of hatching eggs 8 %
hatch after CHEGGY sexing 92.5 %
* Average of 50 commercial hatches (six strains: HyLine Brown, Lohmann Brown, H&N BrownNick, ISA Brown, Bovans Brown, Novogen Brown) in France between January and July 2021

The full study was published in Zootecnica International in March 2022 (download study).



CHEGGY enables hatcheries to determine the sex of layer chicks in an animal welfare friendly and cost-effective way. The fully automated system has an impressively high throughput rate and maximizes egg safety.

  • High accuracy of in ovo sex determination (>96%)
  • Fully automated, high-speed measurement for up to 20,000 eggs per hour
  • Approx. 1/3 of the cost of other methods
  • No risk of contamination or injuries due to the non-invasive process
  • Nearly no hatch losses
  • Environmentally friendly: no expensive consumables required
  • Easy to integrate the animal welfare-friendly stunning of male embryos with AAT’s STUNNY

Hyperspectral Measurement Technology

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Sex determination in the egg with CHEGGY

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Optimization of the CHEGGY process

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