Fig 1. Scanning electron micrographs showing eggshell surface, cross-section, cuticle layer, and cuticle nanospheres of chicken (C), turkey (T), quail (Q), duck (D), goose (G), and ostrich (O).
Cross-sections revealed that the shell was divided into a mammillary layer (ML), palisade layer (PL), and cuticle layer (CL).