Effects of split feeding on performance, egg quality, and bone strength in brown laying hens in aviary system

Brown laying hens are kept in production on average until 80 weeks. In the last phase of the production cycle, however, egg production decreases, and there is a proportional increase in cracked eggs due to decreased shell quality. Laying hens are expected to produce 500 first-quality eggs until 100 wk of age without being molted in extended production cycles. Therefore, problems related to decreased shell quality have to be addressed by genetic selection and also by optimizing nutrition and management. Conventional feeding systems in laying hens might need to be re-evaluated regarding daily Ca requirement, time, and source of its supplementation and absorption. In this experiment, feeding different diets in the first and second half of the d in a split feeding system was tested as a potential strategy to improve shell quality by offering a better match between Ca supplementation and requirements in the laying hen. Although the aim was to keep hens for an extended laying cycle, the flock had to be depopulated at 85 wk due to increased cracked eggs and low performance in the last phase of the experiment. The split feeding system could not maintain shell quality; however, it did show some potential to improve relative shell weight. The practical application of split feeding was challenging in the aviary system, and the flock also experienced health and welfare problems before and during the experiment, which influenced overall performance and the outcome of the experiment. Further long-term studies are needed to address these issues related to shell quality and health of laying hens kept in extended laying cycles.