TUM scientists develop method to prevent day-old chicks from being killed

Breakthrough in the search for an alternative to chick killing

In Germany alone, around 50 million male chicks die every year for economic reasons. (Image: iStockphoto/ Sunnybeach)
In Germany alone, around 50 million male chicks die every year for economic reasons. (Image: iStockphoto/ Sunnybeach)

Research news

For economic reasons, around 50 million male chicks die every year in Germany because they do not lay eggs and provide poor meat. Several teams are looking for alternatives to stop the killing of day-old male chicks. Scientists at the Technical University of Munich (TUM) have developed a method for non-invasive fertility and sex determination that was currently patented.

TUM: What is special about your method in comparison with previously presented procedures that work with a laser or a puncture of the egg, for example?

Professors Benjamin Schusser and Axel Haase: What is special about our method is that, unlike other technologies, it completely dispenses with opening the eggshell. With the help of magnetic resonance imaging, we determine both sex and fertilization status contact-free and non-invasively. Thus, the embryo is not disturbed in development and there is no potential entry point for germs into the egg, as is the case with other methods of sex determination. Furthermore, with magnetic resonance imaging, we're using a technology that has been tested millions of times in human medicine and has no negative effects on the organism.

How early must the sex of the embryos in the egg be determined in order to be able to act in the interests of
animal welfare?

Schusser/ Haase: To date, there exists little reliable data regarding the pain perception of developing chicken embryos. In a statement by the Scientific Services of the German Bundestag (WD) dated 7/31/2017, it is assumed that no sensations are possible before the seventh day of development and that pain perception can safely be assumed to exist from the 15th day of development. For the period between the 7th and 15th day of development, there are opposing opinions, so no conclusive statement is possible. In general, it is desirable to determine the sex as early as possible before the seventh day of development in chicken eggs.

Besides the timely determination of the sex of the chicks, there is another problem:  Many eggs are not fertilized. What causes this?

Schusser/ Haase:
  A distinction must be made between chickens bred for egg production and for meat production. The breeds were selected over decades either by characteristics for the production of eggs or for the production of meat. However, egg and meat production correlate negatively, so only fattening breeds are used in fattening. But these animals show a lower quality of sperm and fitness as their weight increases, which reduces the fertilization rate of the eggs. Thus the fertilization rate of the eggs decreases with increasing age of the parent herd. At present, however, it is only possible to determine whether an embryo has developed or whether the egg was unfertilized by examining the eggs after incubation has begun. The eggs detected as unfertilized must be discarded and may no longer be supplied to the processing industry due to legal requirements. However, if it is possible to determine whether an egg has been fertilized before incubation, the unfertilized eggs can be sorted out and further processed. So there is a useful application for these eggs; incubator capacity can be used for fertilized eggs.  

What is your solution?

Schusser/ Haase:
We have also developed a method for measuring certain magnetic resonance parameters in hen's eggs with the aid of magnetic resonance imaging before incubation in order to be able to distinguish between fertilized and non-fertilized eggs. Using deep learning and artificial intelligence, an algorithm was developed that uses MRI data to distinguish between the fertilization status of eggs.

TUM is currently applying for a patent for your methods. When will it be ready for the market, and can it be used by the poultry industry?

Schusser/ Haase:
Our method of determining the fertilization status is particularly mature. In our case, it will be possible to install a prototype for testing under field conditions within the next year. Gender determination also works, but more research is needed to improve accuracy. The installation of a prototype in a hatchery is expected within the next two years. The magnetic resonance device for determining the fertilization of the eggs and the sex of the embryos is identical; it is simply the image analysis which needs to be optimized for the respective measuring task.

contacts:

Prof. Dr. Axel Haase
Technical University of Munich
Munich School of BioEngineering
Tel: +49 89 289 10822
axel.haase@tum.de   

Prof. Dr. Benjamin Schusser
Technical University of Munich
Reproductive Biotechnology
Tel: +49 8161 71 2027
benjamin.schusser@tum.de