Egg Industry - November 2017 - 14
14 ❙ EggIndustry
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 3 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
has downfalls. The shell is involved in respiration of the embryo, so the method deprives the embryo of 10-12 millimeters of what it is accustomed to. Also, some
weak egg shells do not survive the process.
Researchers make progress on in ovo
chick sexing: www.WATTAgNet.com/
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
Sex determination is 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.
Why researchers are here
Humane methods of day-old chick euthanasia were
approved by the governing bodies of each country's 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,"
EVEN .05 PERCENT
INACCURACY probably isn't
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
"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/
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 of whether this
will seem any more humane to welfare critics. O'Sullivan
explained that this is why researchers are working with
"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. ■
www.WATTAgNet.com ❙ November 2017