It is well known that males for spiking need to be developed enough to be able to be competitive towards the existing old males that are present in the flock. As I always say, we are introducing a bunch of students in the club house of the Hells Angels, perhaps they need some maturity and dominancy before they are brave enough to try to take over the job from the existing males.
Normally (if we don’t use a turbo program for the males) we need to have the males roughly 27 weeks and 4000 gram in body weight to have them being able to compete with the existing males. This means that after transfer the males need to wait approximately 7 weeks before they are ready to be used. There are several options to “store” the males during this times frame.
In theory we could leave the males at the rearing farm for the additional 7 weeks. However, this will block the farm for the arrival of new birds, and if we do bring the new day old chicks when the males for spiking are still present, we run a serious bio-security risk. If we wait with the placement of the new chicks until the spiking males are gone we leave the farm (almost) unused for 7 weeks, and on top of that it ruins our planning of 1 rearing flock for two production flocks.
Traditionally (and still often used) we place the extra males together with the normal males in the production house, and at 26-27 weeks of age we take out the bigger males and use them for spiking. Although this is a practical method that worked well in the past, we see that the high percentage of males at the start of production can cause problems. Too many males create aggressiveness as there are not enough females ready for mating at the start of production. This means that the existing males are fighting for the available females, resulting in lack of condition and dominancy in the males, and wounded and scared females.
To avoid this problem we nowadays often use male houses. At transfer we place the males for spiking in a separate male house at a low density and low light intensity, to avoid competition and fighting. As we want to have the rearing house cleared, we often use a male house on the production farm. Although it works, we see that often still a lot of males are losing condition and at 27 weeks are not ready for spiking. On top of that there is an additional cost involved, as the males need an extra house and extra labor.
Another option is using turbo males. Instead of waiting for 27 weeks to have the males on a target body weight of approximately 4 kg, we reach that body weight at 20 weeks. In this way the males can be ready for spiking when the other males are ready to be placed with the females. The advantages are lower costs (less housing, labor and feed), better male quality (less mortality, better uniformity, better leg quality because of substantially more feed in the period from 10-11 to 20 weeks). But the biggest advantage is easier logistics. If the normal males go to the production house with the females, the turbo males go directly to the older flock for spiking. The only threshold is that from 10-11 weeks onwards the males for spiking have to be housed with a separated feeding system, as they need substantially more feed and feed increases. The benefits are a better bird quality, a cheaper spiking male because of less feed, less labor and eventually a higher stocking density, but also easier logistics.