In-Ovo sexing technologies in hatching eggs :New Technology Could Prevent The Mass Cull Of Male Chicks
It is common practice in the layer industry to cull male day-old-chicks directly after hatching. Male layers are unsuitable for egg production and too resource-inefficient for meat production. A staggering 6.5 billion chicks are killed worldwide every year. These are generally male chicks that are of no economic value. In Ovo has developed technology that can quickly determine the sex of a chick, to ensure that only female chicks are hatched. The practice, however, does raise concerns about animal welfare. An increasing number of initiatives are working on a solution for this challenge by developing technologies to determine the gender of a chicken while still in the egg. The present-day ethical problem with egg production is chick culling of one-day-old male chicks, millions of male chicks that are killed as part of the production process. At the day the chicks hatch from their eggs the chicks are sexed. During chick sexing the day-old chicks are divided into male and female groups. Female chicks can be raised to become egg-laying hens, or broilers fed to be slaughtered for meat, both for human consumption; after the sexing, these female chicks are transported to the rearing farms where they are housed before they go to a laying hen farm or broiler farm. On the other hand, the male chicks are deemed to have much less economic value, as they cannot lay eggs and are usually less suited for meat production; most male chicks are therefore culled on the day they hatch after they have been sexed as male.
In the egg industry, the sex of day-old chicks is determined at the hatchery. Sexing chicks (determining whether they are a hen or a rooster) requires considerable skill and is done at this very early stage to determine their fate.
If strong and healthy, the female chicks are transferred to a site where they are grown to a suitable size and then moved to a laying facility — which could be a cage, free-range or barn set up. Male chicks are considered an unwanted byproduct of egg production and are killed and disposed of shortly after chick sexing at just one day old.
Male chicks are killed for two reasons: they cannot lay eggs and they are not suitable for chicken-meat production. This is because layer hens — and therefore their chicks — are a different breed of poultry to chickens that are bred and raised for meat production. Layer hens are bred to produce eggs whereas meat chickens are bred to grow large breast muscle and legs.
Chick hatcheries breed one or the other type of chick depending on which poultry industry they supply — egg or meat. At the layer hen hatcheries supplying the egg industry with layer hens, the eggs are developed in industrial incubators. Once hatched, the newborn chicks pass down a production line to be sexed and sorted. Sick or weak female chicks and all male chicks are separated from the healthy female chicks and then killed.
Sex determination in the hatching egg
Before the chicks hatch, the sex determination procedures applied to the hatching egg (“in-ovo sex determination”) can be used to check at an early stage whether a female or male chick will hatch from the egg. While eggs in which female chicks develop are incubated further, incubation of hatching eggs with male embryos is terminated. The eggs that have been discarded can then be used as feed, for instance.
The procedures for sex determination in hatching eggs (“in ovo sex determination”) pursue two different approaches:
- In the endocrinological procedure, the eggs are incubated for around nine days. Some liquid is then extracted from each egg without damaging the inside of the egg with the embryo. A biotechnological method is then applied to these samples, enabling the sex to be determined very quickly.
- In the spectroscopic procedure, the eggs are incubated for around four days. Then, a special light beam is sent into the interior of the egg. The sex is determined by analysing the reflected light. Incubation is stopped if a male embryo is detected in the hatching egg. Incubation is continued if a female embryo is detected in the hatching egg so that the chicks hatch after a total of 21 days and then grow to become laying hens. The chicks developing inside the eggs are not aware of the sex determination.
The potential of in-ovo sexing
In-ovo gender determination has the potential to bring an end to the unnecessary killing of billions of male chicks. It is estimated that yearly around 7 billion day-old male chicks are killed. Implementing in-ovo sexing into the poultry industry results in a more animal friendly and more sustainable production. More animal friendly because the day-old male chicks no longer need to be culled, and more sustainable because less energy is used because only the female eggs need to be further incubated after sexing. The male eggs are sorted out and can be used for different purposes such as an alternative high-value protein source.
Solving this challenge has the potential to both address animal welfare concerns and increase sustainability by saving resources. Hatching birds is an energy intensive process, so being able to identify the gender of a chick while it is still in the egg promotes both animal welfare and energy efficiency.
Expected speed of adoption
Our expectation is that as soon as a commercially viable solution becomes available, adoption will start. Germany is expected to be one of the first countries where the technology will be widely adopted. According to a recent court ruling, use of the technology will become mandatory as soon as it is commercially viable. Once that point is reached, other countries in Northwestern Europe may follow. Our current expectation is that the North American market may be slightly later in adopting the technology, but this can change quickly when large retailers and food companies decide to demand its use from their suppliers. We also know that not all markets will accept in-ovo sexing technologies, as the development of life is still disrupted (despite the earlier stage). We already observe a vast growth in the market of growing the male layer chicks for their meat. The organic market in Western Europe expected to adopt fully the growth of the male layer chicks for their chicken meat.
Male-chick culling ban
In the last years, countries started taking legal action to ban male chick-culling. In January 2021, Germany was the first country to successfully outlaw the practice.[7] A few months later, France also banned the one-day-old male chick slaughter.In 2022, the third country, Italy, followed the same steps, prohibiting the practice by 2026.
The discussion has risen around who would be the next country to stop the cruel procedure. Since 2021 the U.S. has been urged to attend the activists’ lobbying that has been done for decades, but so far no progress has been made.
Early technological breakthroughs
Academic research
For a long time, it was held impossible to determine the sex of the hatching egg before or during the hatching process. The poultry sector has been working on this for years in order to be able to phase out chick culling in the interest of animal welfare.
Research has been conducted to achieve this goal. The first study on the matter, was published in 2013, for in-ovo sexing on day 9 of incubation. The researched procedure, later called bio-marker detection, used a hormonal test for the allantoic fluid of brown layers’ eggs. Further research was done by Prof. Dr. Einspanier following the same methodology. It is important to mention that hatcheability is affected by this in-ovo sexing method, as reported by Dr. Einspeiner.
n 2016, the fluorescence spectroscopy methodology[] was developed, it analyzes the extraembryonic blood to determine the sex of the embryo through its blood wavelength. The supervised egg classification by a PC with a 93% error rate was able to determine the sex of 380 eggs at 3.5 incubation day. A variation of this methodology was explored in 2017. When the pattern analysis in hypersepctral images methodology was researched. First, the eggs would be candled with halogen lamps. Then, a hyperspectral camera would collect the transmitted light and the eggs would be classified using a linear discriminant analysis. This methodology could perform in-ovo sexing from 11-day up to 14-day embryos with a 97% accuracy.
2019 a new methodology was developed, AI-powered imaging. By combining AI and MRI together to perform in-ovo sexing of 12-day-old eggs with 95% accuracy level. Since 2007 MRI was used as a valuable tool for studying egg development in a contactless manner. Yet it would not be until it was combined with AI that it could be used for large-scale purposes.
First commercial application
In 2018 Seleggt was the first company to succeed in commercial in-ovo sexing. Seleggt managed to sex the hatching eggs on day 9 of the incubation process with a hormone test.The method is based on the fundamental research of Prof. Dr. Einspanier at Leipzig University.From 8 November 2018, consumption eggs that are laid by the hens that have been sexed with the Seleggt method are to be found on the shelves of the German supermarket REWE, in the Berlin region. The eggs that have been sexed with the Seleggt method are sold under the label “Respeggt”. This label guarantees the promise “Free of chick culling”.Since 2018, Respeggt eggs have been available in Germany, France, and the Netherlands.
From then on more companies have followed and thrived, implementing different methodologies and technologies for in-ovo sexing. Their descriptions will be added below.
Sex determination methods
The in-ovo sexing technologies have evolved into two main categories: invasive and non-invasive. An invasive technology is any technology that creates damage to the egg through intrusive sampling ans biochemical analysis for the in-ovo sexing process.Examples of these are biomarker detection, PCR, spectroscopy, and endocrine method. The main drawbacks of invasive procedures is that, they may affect the eggs’ hatcheability and that the process implies a risk for bacterial infection.On the other hand, non-invasive technologies, have a contactless in-ovo sexing procedure (e.g. AI-powered imaging) are free of this previous risks.
Invasive Technologies
Bio-marker detection (Seleggt, In Ovo)
The Dutch–German company Seleggt measures a substance that is a ‘biomarker’ for the sex through a small hole in the eggshell on day 9 after fertilisation. Mixed with fluid from fertilised eggs, this marker changes blue for a male and white for a female, with a 98.5% accuracy rate. As of May 2019, Seleggt sexed one egg per second (3,600 an hour) and thus enabled 30,000 ‘no-kill’ female chicks to hatch in Germany every week. The German Federal Ministry of Food and Agriculture (BMEL) has invested 5 million euros in the development of the Seleggt technology.
Another Dutch company is In Ovo, a spin-off of Leiden University, Netherlands. This company was founded in 2013 by students Wouter Bruins (biology) and Wil Stutterheim (biomedical sciences) and, just like Seleggt, uses a small amount of liquid from the hatching egg and determines whether it is a male or female hatching egg by means of biomarker detection on the 9th day. By January 2020, In Ovo was capable of sexing 1,500 eggs an hour (0.42 per second), but the Dutch poultry sector required 40,000 eggs an hour, so further innovation was necessary.In Ovo received millions of euros in research investments, mostly from German chemicals company Evonik, Singaporese venture capital company Visvires New Protein, and Rabobank Leiden-Katwijk.
PCR (Plantegg)
The German company Plantegg uses a PCR method, which uses DNA to determine whether the hatching egg is male or female. Like In Ovo and Seleggt, this method determines the sex on day 9 of the incubation process. This method is expected to be ready for use by the end of 2020.
Non-invasive technologies
Spectroscopy (AAT, Projet Soo, Hypereye)
Another German company, Agri Advanced Technologies (AAT), uses spectroscopy to determine the sex of the egg. The hatching egg is examined with by light beam, with a hyperspectral measuring technology the sex is determined on the basis of the calculated light spectrum. This method works for brown hatching eggs and can take place from the 13th day of the hatching process.AAT’s goal is to eventually be able to sex eggs at the 4th day.The German Agriculture Ministry has also invested in AAT’s technological development.
The French company Tronico, based in La Roche-sur-Yon, collaborates with the French National Centre for Scientific Research (CNRS) on Projet Soo, which employs a mix of spectroscopy and the use of biosensors with the target of achieving 90% accuracy in ovo sexing at 9 days of incubation by the end of 2019. In 2017, French Agriculture Minister Stéphane Le Foll granted Projet Soo 4.3 million euros to finance its egg sexing research.
Hypereye is a Canadian spectroscopic technology that is being developed by the Egg Research Development Foundation (ERDF), initially funded by Poultry Industry Council in Ontario and later by Egg Farmers of Ontario (EFO).It aims to achieve a 99% accuracy rate and to process 30,000–50,000 eggs per hour (8.3–13.9 eggs per second).In 2018, Canadian Agriculture Minister Lawrence MacAulay announced an $844,000 investment in the research project to stimulate its development.
Ai-powered imaging (Orbem)
Based on years of scientific research at the interface of AI, imaging technology and embryonic poultry development, Orbem was founded in 2019 as a spin-off from the Technical University of Munich. Orbem uses AI-powered MRI to conduct in-ovo sexing on day 12 – 13 of incubation, with a throughput of up to 24,000 eggs per hour. The solution applies equally to brown and white eggs . The solution is contactless and has no effect on the hatchability rate.
Two installations with a capacity of 6,000 and 12,000 eggs per hour will be fully operational at two French locations in January 2023 in line with French regulatory requirements. Orbem has entered a strategic partnership with the Vencomatic Group (NL) for end-to-end automation of the process, which includes financing facilitated by the Vencomatic Group of up to 15 Million Euros for equipment to be deployed at customer sites throughout Europe.This allows hatcheries to use the combined solution without any upfront investment just based on a performance fee per egg.
Alternative:
male broilersAnother alternative to preventing chick kills is fattening rooster chickens, which is what the Dutch company Kipster does. Hens and roosters are separated in the hatchery as usual. The cocks then go to a Kipster broiler farm where the cocks are fed and slaughtered when they reach their target weight.
Differences between technologies
When looking at the in-ovo sexing technologies in this field it is important to have an eye for the following aspects:
- Invasive or non-invasive: Some technologies require making a hole in the egg. This is a concern, since it creates a risk for contamination and lower hatchability. Therefore, non-invasive technologies are preferred.
- High accuracy: The technology must be very accurate in determining the gender. The accuracy needs to be in line with existing levels of accuracy when sexing chicks after they hatch.
- The sooner the better: The sooner the sex can be determined in the egg the better. To address animal welfare concerns, eggs should be sexed before the age of pain sensation. Although scientists disagree about the exact number of days at which pain is felt, it is clear sooner is better. Obviously, the optimal solution, both for animal welfare and efficiency, would be to do in-ovo egg sexing pre-incubation.
- High speed of sexing eggs: To function in a commercial hatchery, the speed at which eggs need to be sexed must be very high. This is particularly important if sexing happens when eggs have already been in the incubator – to prevent them from losing too much heat. So, technologies need to operate at high speed.
- Small and robust equipment required (for hatchery environment): Going from a laboratory set-up to a commercial hatchery operation is a very difficult step to take. Successful integration in a hatchery requires a robust and easy to clean machine. The technology will have to be fitted in existing facilities.
Ongoing initiatives and their approaches
An ever-increasing number of initiatives are trying to determine the sex of a chicken before they hatch. Hendrix Genetics is actively following the most promising of these around the world. Several different approaches on in-ovo sexing are being tested:
- Spectroscopic detection: Spectroscopy is the technique of splitting light (or more precisely electromagnetic radiation) into its constituent wavelengths (a spectrum) in much the same way as a prism splits light into a rainbow of colors. It requires shining a light beam of laser through the eggshell or a hole in the egg. Via image analysis, the gender is determined. Although training the software to be sufficiently accurate requires tremendous amounts of data and therefore time, this technology does offer the prospect of early identification.
- Biomarker detection: This form of analysis requires taking a fluid from the egg, mixing it with a biomarker, and analyzing the resulting sample. In most cases, allantoic fluid is withdrawn. The fluid is then used for a test that allows to see the gender. There are several different tests being investigated or developed. Most of these tests work after day 7 or 8.
- Gene editing: A few projects are working on a solution using gene editing. The regulatory framework for this is still unclear as is consumer acceptance. On the other hand, if it were to be widely accepted, the benefits of such a technology would be that it is non-invasive and provides opportunity for pre-incubation egg sex detection.
Technologies closest to the market
This list is by no means exhaustive, but it is a selection to demonstrate the variety of approaches.
- Seleggt
The first company to reach the market was Seleggt. Since November 2018, eggs have been sold under the consumer brand Respeggt. The Respeggt label promises: “Free of Chick Culling”. They launched in 200+ supermarkets in the Berlin area and have since significantly expanded their coverage of the German market. Since the summer of 2019, the eggs are also available in Carrefour supermarkets in the Paris region in France. and since 2020 also in the Netherlands. The price is comparable to a free-range egg.
The in-ovo sexing technology has been developed in a joint venture between German retailer the REWE group, Dutch technology company HatchTech, and professor Einspanier from the University of Leipzig. On day 8 of the incubation, a laser beam burns a 0.3mm-wide hole in the shell. Then, air pressure is applied to the shell exterior, pushing a drop of fluid out of the hole. This fluid is analyzed using a proprietary biomarker, which allows them to determine the sex.
- In Ovo
The Dutch In Ovo company was founded in 2013 by biomedical scientist Wil Stutterheim and biologist Wouter Bruins, who met at the University of Leiden. The in-ovo sexing technology they use is based on biomarkers and is invasive. A sample is taken from each egg, mixed with a biomarker, and examined by mass spectrometry. At the end of 2018, Evonik and VisVires New Protein invested in In Ovo, along with the participation of Leiden University. With the investment capital, In Ovo plans to develop the technology to the stage where it can be applied on the commercial scale in hatcheries.
- PLANTegg
The aim of the PLANTegg innovative process is the gender determination in chicken eggs. This avoids the killing of hatched male day-old chicks in hatcheries during the production of laying hens. New technologies have been developed and combined for the so-called PLANTegg process – a PCR-based method for gender determination of hatching eggs. This molecular genetic method is based on the fact that the chickens have different gender chromosomes. The PCR technology makes the genetic differences, to be found in the DNA of the allantoic fluid, visible. The gender can thus be determined at an early stage of incubation with high precision and very quickly (within one hour). The eggs from which male chicks would hatch can then be sorted out early and used for other purposes. The method can be automated, is infinitely scalable and can therefore be used in both small and large hatcheries.
- Hypereye
Hypereye is a patented scanning in-ovo sexing technology that uses non-invasive hyperspectral imaging. This is done at day 0, pre-incubation. The technology was developed by Michael Ngadi at McGill University in Canada, with funding from Ontario Poultry Industry Council, Egg Farmers of Ontario and Livestock Research Innovation Corporation. They are currently testing prototypes to achieve the same accuracy and speed at a commercial scale as seen in the laboratory.
Potential source of new initiatives on in-ovo sexing
While ongoing initiatives on in-ovo sexing continue developing their technology further, from the laboratory to a commercial prototype, to eventually reach the market, new projects and initiatives keep popping up. In many cases, these new entrants are supported with funding from industry and governments.
One such source of new initiatives on in-ovo sexing is the competition organized by the Foundation for Feed and Agriculture Research (FFAR). They are awarding an Egg-Tech Prize to help organizations and individuals solve the scientifically and technologically complex issue of identifying the sex of a chick in the egg prior to certain embryo developmental milestones.
At the end of 2019, they announced that in Phase I of the competition, they awarded USD $1,056,957 to six organizations. Participating researchers are from around the globe and include academics, private research companies, and USDA Agriculture Research Service. The methods on in-ovo sexing these different groups will explore are diverse and include volatile organic compounds, reaction mass spectrometry, and magnetic resonance imagining. In Phase II of the prize competition, contestants will develop and validate a working prototype that meets the criteria that are set. FFAR will accept Phase II submissions in early 2021.
New Technology Could Prevent The Mass Cull Of Male Chicks
Recent studies show that in-ovo gender determination of incubated eggs can provide a beneficial substitute for the large-scale culling of male chicks in layer hen production. However, the technology raises ethical concerns relating to the sensitivity of the embryo, the use of screened-out eggs and the accuracy of in-ovo screening.
In-ovo technology enables male chicks to be identified within the egg during the incubation period. Recent developments show that this technology is expected to be ready for market on a large scale in most countries where the technology allows this and where animal welfare is a priority.
Looking at the methods in a nutshell, the first is a method that determines gender at day 4 of incubation with a spectroscopic analysis of extra-embryonic blood vessels. The second method analyses the estradiol content of the allantoic fluid on day 9 of incubation. The third option sets out to analyse the gender through magnetic resonance – offering the ability to sex eggs from the first day of incubation.
A study to determine consumer attitudes
To thoroughly investigate consumer attitudes towards this new technology, a study was conducted in Germany with a representative sample of 482 respondents or consumers in which an anonymous online survey was developed and made available to the participants.
Benefits of in ovo feeding
The nutritional demand of embryos and early aged chicks has changed over decades. Early nutrition programming is one of the latest and successful methods to feed embryos and recently hatched chicks to prepare chickens with a healthy gut, favourable microbiota, improved immunity, and overall improved growth performance.
Among a representative sample of participants, their geographical context, age and level of education were also taken into account. The researchers believe their findings will be useful to stakeholders in poultry production who are considering the implementation of in-ovo gender determination as an ethically-acceptable substitute to male chick culling.
Stage of in-ovo screening
The stage of embryo development at which the in-ovo screening is performed is as important to the technologists as it is to the consumers. The study revealed that in-ovo gender determination at each proposed day of incubation (day 1, day 4, and day 9) is preferred to chick culling. The screening on day 1 and day 4 was significantly preferred to screening at day 9. This shows that public acceptance of in-ovo screening largely depends on when during embryonic development the screening is performed.
Conscious pain perception
It can be assumed that the ethical value given to the chicken embryo increases with embryonic development. The participants indicated that the destruction of embryos should take place at an early stage of development, before conscious pain perception is possible. However, pain perception is a subject that is still under discussion. It was found that 41% of the respondents would approve of the technology if it could be carried out with certainty before the onset of pain perception.
Pictures influence consumers
Consumer preferences for in-ovo screening was first tested using plain text only and then with pictures of a chick or the incubated eggs at the corresponding stages of development. What was discovered is that the preference for early (day 1 and day 4) gender determination increased significantly because of the pictures provided. Screening at day 9 and day 21 (hatching time) was less preferred when pictures were included.
Sex reassignment in the egg
Israeli start-up Soos has developed a technique to alter the sex of embryos from male to female in the hatchery and thus tackle the culling of male chicks.
There was also a decrease in willingness-to-pay for the implementation of the technology if the screening is performed at day 9. Willingness was highest at day 1, followed by day 4. The suggested reason for this was that pictures say more than words – besides providing information, they can quickly evoke associations and feelings, and are remembered better and for a longer time than text.
Drivers of debate
In a mass media environment, pictures are readily available and move rapidly through digital channels, which makes them drivers of wider debates in society. It was also stated that the way the pictures are taken and how systems and animals are depicted influences overall perceptions, especially among people who are not familiar with the subject matter.
Screening errors
The survey showed that a high error rate of in-ovo gender determination or the lack of a meaningful use for incubated eggs decreases the approval rate for in-ovo gender determination to an extent, such that no positive willingness-to-pay for implementation of the technology remains. Both a meaningful use of by-products and a high rate of accuracy are crucial factors for the acceptance of in-ovo gender determination.
This study presented 3 uses of screened-out eggs, namely the chemical industry, as pet food, and as livestock fodder. The results showed that the use of screened-out eggs in the chemical industry was the least desirable, while use as pet food was the most preferred. It was suggested that this could be because consumers are more familiar with these uses or that their utilisation as a nutrient is considered superior to utilisation as an industry product.
Technology and animal welfare
Among the respondents, 20% were referred to as ‘technology-savvy’ as they were more concerned with technological advances in agriculture and animal welfare improvements. This group was also strongly against chick culling and greatly favoured the use of screened-out eggs as pet food but disapproved of their use in the chemical industry. In addition, this group was more focused on legislation to include these new developments.
Alternative use of male chicks
As found in this study, a comparison of in-ovo gender determination and dual-use poultry production reveals a willingness-to-pay for the implementation of both alternatives, but with the willingness-to-pay being higher for in-ovo gender determination. “Dual-use poultry with male chicks in free-range husbandry is the best alternative to the current culling practice” was the response of 27% of the consumers. In addition, 20% of the respondents indicated that they might accept chick culling under certain circumstances, for example, the use of male chicks as pet food.
An ethically acceptable alternative to chick culling?
In conclusion, the development of a technology which enables chicken embryos to be sexed at an early stage of development may be promising to meet consumer preferences. The results of this survey revealed a considerable willingness-to-pay for the in-ovo technology on the part of the consumers.
The preference becomes clearer when consumers are presented with pictures of incubated eggs or a chick. The findings further imply that a high level of screening accuracy and the meaningful use of screened-out eggs should be clearly communicated to consumers, as these are crucial factors for the acceptance of in-ovo screening as an ethically acceptable alternative to chick culling.
PROF. HK DEKA, EDINBURG
