In-ovo sexing 2020 pledge unlikely to be met

The United Egg Producers promise of 2020 to have in-ovo sexing in commercial hatcheries is overly ambitious given the progress of research currently underway.

Lukas Blazek, Dreamstime
Lukas Blazek, Dreamstime

The United Egg Producers' promise to have in-ovo sexing in commercial hatcheries by 2020 is overly ambitious given the progress of research currently underway, according to  Dr. Neil O’Sullivan, director of global product management, Hy-Line International.

The egg industry is working vigorously to move to in-ovo sexing -- the ability to sex eggs before incubation -- but he told the audience at USPOULTRY's 2017 Live Production, Welfare and Biosecurity Seminar, on September 19 in Nashville, Tennessee, that the technology isn't ready for commercialization yet.

The humane euthanasia of day-old chicks has been challenged by animal welfare activists in recent years.

“Research has been underway to find methods to either in-ovo sex during the incubation process or, ideally, to gender sort the eggs prior to incubation,” O’Sullivan said.

Researchers all over the world are working to find a solution. O’Sullivan explained that, from what he can tell, the researchers in Canada are furthest along in the process. However, he explained that the group working on the project there has not opened the study to outside partners.

There is a cutoff date of 18 days of incubation for sexing embryos based on accepted practices used in the biomedical industry where chicken embryos are used in the production of some vaccines. To keep media and animal rights activist pleased, it is important to cut off the testing of eggs before they start to look too much like chicks, O’Sullivan explained. “It would be very hard to justify it if it isn’t acceptable in the biomedical industry,” he said.

Two potential methods

In-ovo gender determination based on the hormone level in the allantoic fluid is known as endocrinological testing. The process takes place on day 10 of incubation. This ELISA test looks for estronsulphate concentration in a sample of fluid which is removed from the egg.

“From day nine onward, you can find significant differences in the concentration of estronsulphate  between males and females,” O’Sullivan explained. The perks to this method is that it offers good accuracy and a loss in fertility of under five percent. However, this type of testing still has some kinks to work out before the method can be considered useful.  

“With current evaluation, we would like to get things done before nine days of age,” O’Sullivan said. The testing process takes too much time and poses researchers with questions like, how do I keep the eggs warm, where do I put them, do I need to turn them and so forth. “We start to get into hatchery problems,” said O’Sullivan. This method is also very expensive, he noted.

The other method is called Infrared Raman Spectroscopy, which measures how the molecules of a substance react to photons of light. The testing is possible from day three after brooding starts. It is a non-contact measurement. However, a hole must be made in the shell at the sharp pole approximately 12 millimeters in diameter. The hole is then covered with surgical tape. “We would like the hole to be down to 4 millimeters,” O’Sullivan said.

Managing the hole with surgical tape is working but it does have down falls. The shell is involved in respiration of the embryo, so we are depriving the embryo of 10-12 millimeters of what it is accustomed to. Also, some weak egg shells do not survive the process.

Unlike the red blood cells of mammals, a bird's red blood cells have a nucleus. In birds, males are homomorphic at the sex chromosome (ZZ) and the females are heteromorphic (ZW). The Z chromosome is larger than the W chromosome, so males have more DNA than females and this difference can be detected using Infared Raman Spectroscopy, because the system measures the backscattered radiation.

Measurement is not possible before incubation. “At three days there is a reduction in hatchability,” he said. The size of the hole has a negative impact on hatchability. However, the Spectroscopy method itself has no/low influence on hatchability. The losses are currently just too high for this method to be deemed realistic.

“This is a nice method because it’s non-contact and the duration of the measurement is very short,” said O’Sullivan. Sex determination runs at about 95 percent accurate. However, O’Sullivan suggests that the accuracy rate needs to be higher than 95 percent. “Even .05 percent inaccuracy probably isn’t accurate enough,” he said.

There are nearly no costs for consumables. Costs should only consist of biocompatible adhesive tape. No information is available regarding the machinery costs at this time.

Why researchers are here

Currently humane methods of day old chick euthanasia were approved by the governing bodies of each countries’ veterinary associations. “In the U.S. American Veterinary Medical Association Guidelines on euthanasia (June 2007) included methods such as; inhalant agents (carbon dioxide, nitrogen/argon mixes), maceration, and cervical dislocation,” O’Sullivan explained.

Future of in-ovo sexing

Future technology may allow egg sexing prior to incubation. However, O’Sullivan fears that the given time combined with funds and cost of the research may continue to limit the industry’s ability to sex eggs.

Producers have posed the question if this will seem any more humane to welfare critics. O’Sullivan explained that this is why researchers are working with biomedical guidelines.

“This technology will more than likely have to be approved as an FDA medical device,” O’Sullivan said. This may extend the time for getting in-ovo sexing started even longer.

You’ll also learn about:

Page 1 of 1576
Next Page