Manipulating egg weight and shell quality with phase feeding

摘要

A marketable egg weight and stable shell right to the end of the laying period are not only important elements in the breeding strategy. They also require constant support through a balanced nutrient supply, which must be tailored to the hens' age and level of production. Often the preferred shell egg weight grades are classes M and L, which generate the most favourable cost-income ratio. S-eggs command lower prices while XL-eggs tend to have inferior shell strength, especially in older flocks. Topbreeding products are genetically predisposed to achieve a rapid early egg weight increase (60 g before 30 weeks of age) with an excellent laying rate of 95 to 96 percent. As well as these performance improvements, selective breeding over the last 10 years has placed additional emphasis on shell stability.