When we need males for spiking of a broiler breeder flock, we often use males that we have extra out of the normal rearing program of a new flock. In many cases we receive with a new breeder flock more males than needed for the number of females, to be sure that there are enough good males available at the moment of placement. When we conclude that at the end of the rearing period there will be more males available than needed for the flock, the surplus can be used for spiking an older flock.
But that does create a practical problem. At the end of rearing (let's say at 20 weeks of age) the males are not mature enough for spiking, we need to keep them a couple of weeks until they have enough body weight (for instance 4 kg on average) to be able to compete with the existing older males in the flock. That means that from 20 weeks onwards we need to "store" those males somewhere to let them develop.
If we have a separate male house we can place them there, but there will be a lot of competition among those young developing males, and if we are not careful a number of males will lose condition and dominancy and will not be useful for spiking anymore.
Another option is to transfer all the males with the females to the production house, keep them there several weeks and take the extra males out when they are ready for spiking. This is relatively easy but for a number of weeks there will be a surplus of males in the female house, and if the males are too agressive or the females are a bit delayed in development, it can result in damaged and scared females with frustrated and agressive males.
But the problem is actually that we let the males develop in the same speed as the females. The females have to develop slowly to avoid overstimulation, which can result in more double yolks, prolapses, egg peritonitis and mortality. But the males by itself do not have to develop slow, unless it is needed to not be too early for the females. Males can develop much faster than females, and if they reach a good body weight for spiking at the age where they normally are mixed with the young females, they can be used for spiking right away without the need to let them wait and develop for a couple of weeks.
If we can separate a group of males in rearing, we can get them ready for spiking at an earlier age. If we select at 10-11 weeks the heaviest part of the male population and place them in a separate part of the rearing house, we can increase the feed amount from that moment on siginificantly and grow them to approximately 4 kg at 20 weeks, instead of following the usual rearing program for males. Although these males are relatively young, at 20 weeks and 4 kg they will be mature and developed enough to do the spiking job. If possible we can give also light stimulate them one or two weeks before placement, but if they are in the same house as the normal males there is no problem to keep them on the same light program as the normal males and let them be light stimulated at arrival in the production house.
An advantage of this "turbo program" is that the second part of the rearing program for these males is much more relaxed. They get more feed as we do not have to restrict them that severe to delay them. That works positive on development, competition, uniformity and mortality. And on top of that we dont have the problem that we need to "store" these males a couple of weeks, with all the difficulties that it brings.