Spiking
Spiking is usually defined as the
addition of new males to a 40 to 45
week-old broiler breeder flock to
compensate for the age-related decline
in fertility. As a general rule, males are
added to compensate for mortality and
to re-establish the original male to
female ratio. Alternatively, 5 to 10%
of old males are replaced due to their
poor physical condition. Generally,
the males that are added or used as
replacements are 25 to 28 weeks old,
have been grown on a pullet farm and represented only 75% of the males
present. This indicates that for the
first 4-6 weeks after spiking the
young males served merely as a
stimulus for the old males and their
input to the flock fertility was small.
After 6 weeks, however, the young
males took over and started to
significantly affect the overall mating
activity.