Increasing protein consumption can be handled from two point. In general adequate protein consumption is essential for  breeders to reach sexual maturity in time and thus egg production in terms of laying rate and egg weight, while decreasing the protein consumption may retard sexual maturity and laying rate and egg weight depends on degree of the reduction of protein consumption. In the case of increasing protein consumption we can see the contrary trend such as early sexual maturity, increasing egg weight, not egg number, increasing obesity and collapse in broiler breeders. From my PhD work broiler breeders are very sensitive to nutrient intakes and one should take of their nutrient needs during the entire life and follow as far as possible the breeder guide for nutrient allotments.  

I believe there is because from our farm, we noticed greater than 5% dead of the young chicks. When we increase percentage proteins by 10% in the meals of the layers, the mortality rate decreased to less than 3% and the chicks were very healthy to maturity. By inference, it can be concluded that protein consumption to a certain extent has a positve effect during growing period of hatching eggs. Also bare in mind that excess of anything will have negative impact(s).

Thank you

We have started publishing our recent work on this in Poultry Science. Rick van Emous from Wageningen University also has recent work in this area. We varied protein and energy levels in the pullet diet to test the long-term impact on support for reproduction vs. muscle growth and fatness. While protein level in the pullet diet did not affect egg numbers or fertility, it did affect broiler offspring yield in the 28 to 36 week range (the only ages we did offspring trials). Breeder nutrition did not affect broiler offspring yield, but pullet nutrition did. We used Ross 708 for the project.