WATT PoultryUSA - April 2018 - 60
60 ❙ WATTPoultryUSA
Genetic improvements against
poultry myopathies foreseen
A decrease of breast meat myopathies is expected in 2018.
Modern poultry production solved several challenges from
the past, and now the focus is on combating breast meat
myopathies, according to Dr. Alejandro Corzo, senior poultry nutrition specialist at Aviagen, speaking about how his
company is using genetic selection to fight emerging myopathies, like wooden breast, during his presentation at the
2018 International Production & Processing Expo's Poultry
Seminar in Spanish on January 30.
Aviagen focused on using genetic selection to detect breast myopathies. There three main ones are:
■ White striping
■ Stringy spongy
■ Wooden breast
Wooden breast is the most common, where muscular fibers display great variations, with hypercontracted
fibers and connective tissue giving meat its characteristic hardness, along with low vascularity.
Although wooden breast does not represent a public
health problem, it is a meat quality problem.
One strategy aimed at solving it is making selections at the processing plant and picking brothers and
sisters of good pedigrees, which involves both tactile
and quantitative evaluations with specialized equipment. Selections of live animals are also made by palpation in the pectoralis major muscle to detect different
levels of myopathies and to evaluate breast firmness.
However, selected candidates must still be good in
terms of feed conversion and other key characteristics.
When will the changes be seen?
Corzo makes it clear that breat myopathies will not
be eliminated entirely. But, by mid-2018, a reduction of
about 10 to 15 percent will be seen, becoming slightly
more gradual in the next four to six years.
Other evaluations and strategies
Corzo said Aviagen has made a series of evaluations. It detected there is a higher prevalence of
wooden breast as the bird grows larger. That is to say,
the longer it takes for the chicken to be slaughtered, the
more likely there it is to exhibit wooden breast.
Corzo said the breeding company is using the following strategies to help solve the myopathy problem:
■ Quantitative feed restriction: A feed restriction
of 5-10 percent, with respect to the previous day's
ad libitum consumption, causes weight gain to decrease slightly, but myopathies are reduced 43-57
percent. A 5 percent restriction at the starting phase
and lesving birds ad lib worsened the incidence.
feed restriction: A decrease in digest■
ible lysine content in different phases resulted in a
white striping decrease.
■ Antioxidant supplementation: Supplementation of
oxidized fats with antioxidants (ethoxyquin, vitamin C and E, and ethoxyquin with vitamin C and
E) caused myopathies to be reduced by almost half.
■ Phytase: Different doses gave a very slight numerical response. With a phytase superdose, no increases
or improvements in wooden breast were observed.
Other studies showed significant differences.
■ Other compounds: Aviagen studied guanidinoacetic acid, the relationship of arginine-to-lysine ratio,
variations in anticoccidial programs, selenium and
organic minerals, but without conclusive results. ■
www.WATTAgNet.com ❙ April 2018