New frontiers in egg layer
Whole Genome Selection allows rapid generation turnaround time for egg
layer populations, which translates into better rates of genetic gain.
Neil O’Sullivan, Ph.D.
Modern egg layer breeding developed in the early 20th century, founded on a combination of traditional breeding methods with purelines, than combining
the use of hybridization principles learned
from corn breeders. The egg layer breeding
industry, along with all animal breeding, has
continued to evolve and incorporate new
methodologies as they are developed by research in genetics. Progress has been rapid
in the last 75 years. Will we continue to see
sustained rates of genetic progress in egg layers? Will progress plateau? Or can we expect
accelerated rates of genetic progress?
Currently egg layers can continue to improve with 2-3 more eggs added to the life
cycle of the layer in each generation. One
percent improvement in feed conversion
per generation, 0.1% improvement in grow
house livability and 0.2% improvement in
adult livability continue to be sustained each
generation. Improvements in all egg quality
traits, such as reduction in percentage of un-dergrade eggs, improved shell appearance in
color and shell strength will continue along
for nest usage, a trait ignored from the 1960s
to the turn of the current century. All these
traits can be measured, evaluated, and therefore can be selected for improvement using
applications in industrial breeding programs.
It requires industry geneticists to be as comfortable working in the chicken house as in
the halls of higher learning of academia.
Hens can now have progeny with multiple sires, opening up more genetic variation.
current tools of animal breeding.
In animal breeding, however, the only
constant is change. Housing and production
systems continue to change and evolve for
egg layers, from small backyard ;ocks of the
early 20th century, to ;oor systems, to cage
systems by the 1960s, and now to
enriched cages, aviary systems, or
modern ;oor systems for the 21st
century. Breeders must be on the
forefront of any change in order to
respond to these changes demanded
by the egg producers and the egg producers’
Selections made on the current generations of breeders must re;ect the needs of the
customers three to four years from now. This
responsiveness to change requires a close
industry relationship of the geneticists in the
breeding companies with the trend markers of the egg industry. It requires breeding
companies to continue close collaborative
research with academic institutions to convert new ;ndings in genetics into practical
More from Dr. O’Sullivan “Optimizing production from floor-housed pullets and hens” www.WATTAgNet.com/10631.html
Recent collaborative work between academic scientists from Iowa State University,
University of Wisconsin at Madison, and Edinburgh University along with industry scientists
of Hy-Line International, Lohmann Tierzucht
and Aviagen, has been making new breakthroughs in Whole Genome Selection (WGS).
This rapidly advancing new frontier of animal
breeding has come about due to the availability
of high throughput genotyping of birds with
very large numbers of genotypes being able to
now be measured on each and every bird.
with improved albumin quality, increased
egg solids and continued reduction in inclusions in the egg such as meat or blood spots.
8 • Industry Egg • December 2009 • www.WATTAgNet.com
Improvements go beyond
Along with these production traits improvements, continuous improvements will
continue in bird social behavior, with better
feather cover, reduced feather picking and
cannibalism. Birds are again being selected
Genotypes can estimate
After the chicken genome was sequenced
in 2004, millions of Single Nucleotide Polymorphisms (SNP) were developed, allowing
the creation of speci;c SNP panels tailored
to egg layer chicken lines to be developed by
groups like Hy-Line, Lohmann and Aviagen
working together. These SNP panels allow
whole genome scans to be performed on in-