According to researchers at the University of California Davis and Sensit Ventures Inc. can the sex of fertilized chicken eggs be determined using volatile chemicals emitted by the shell. This method could help divert male eggs to other uses, reducing waste and environmental impact.

The approach detects volatile organic compounds released by the developing embryo and is based on a sensing chip technology developed by Professor Cristina Davis’ lab at UC Davis. Sensit wants to commercialize this technology for various applications, including agriculture and medicine. Researchers have developed a suction cup sniffer to analyze air samples from eggs without opening them.

The suction cups, initially used for industrial egg handling, were adapted for this purpose. The air samples were analyzed by gas chromatography/mass spectrometry in the lab of Professor Cristina Davis at UC Davis.

The sex of the eggs was confirmed through DNA analysis in Professor Huajin Zhou’s lab. With this method, male and female embryos could be identified with an accuracy of 80% after eight days of incubation.

The suction cup sampling process can be performed quickly in rows, efficiently testing multiple eggs at the same time.

The hardware platform invented at UC Davis has the potential to be integrated into hatcheries, said Tom Turpen, the president and CEO of Sensit Ventures. Founded in 2015 with support from UC Davis, Sensit Ventures has benefited from access to on-campus resources for their research.

Researchers used an active sampling method to collect volatile chemicals from chicken eggs. The eggs were placed in a sealed chamber and a vacuum pump was used to draw in air. The air was then passed through a series of sorption tubes, which retained the volatile chemicals. The sorbent tubes were then analyzed by gas chromatography-mass spectrometry (GC-MS) to identify the volatile chemicals.

They collected samples from 100 chicken eggs, of which 50 were male and 50 were female. They found that the male eggs produced a different profile of volatile chemicals than the female eggs. The main difference was the presence of dihydrotestosterone in the male eggs.

They used a statistical method called discriminant analysis to classify the eggs by sex. Discriminant analysis is a statistical technique that can distinguish between two or more groups of data. In this case, we used discriminant analysis to distinguish between male and female eggs based on volatile chemical profile.

They found that we could classify the eggs with an accuracy of 80%. This means that if they randomly selected 100 eggs, they would correctly identify the sex of 80 of them.

The results show that it is possible to sex chicken eggs early in the hatching period by analyzing the volatile chemicals they emit. This method is non-invasive and does not damage the embryos. Producers could use it to identify and cull male embryos before they hatch, reducing waste and improving profitability.

This method is still under development and further research is needed to improve the accuracy and efficiency of the method. However, the results of this study are promising and this method could have a significant impact on the poultry industry.

Magazine reference:

  1. Eva Borras, Ying Wang, Priyanka Shah, et al. An active sampling of volatile chemicals for non-invasive classification of chicken eggs by sex at an early stage of incubation. Plop ONE. DOI:10.1371/journal.pone.0285726