Rapid quantification of avian eggshell microstructure and crystallographic-texture using two-dimensional X-ray diffraction.

1. It is important to quantify eggshell microstructure because it may influence eggshell mechanical properties and could be of importance for eggshell quality assessment. It also provides information about changes in eggshell associated with different hen physiological conditions. 2. This paper describes an alternative methodology which, based on 2D X-ray diffraction, allows eggshell microstructure quantification (for example, crystal size and orientation) much more efficiently than using traditional techniques (optical or scanning electron microscopy and conventional X-ray diffraction). 3. For such analyses, an X-ray diffractometer equipped with an area detector is used. Such equipment collects the diffraction pattern of the sample in one single exposure (taking a few tens of seconds), thus considerably reducing data acquisition time. 4. The two-dimensional diffraction patterns obtained contain detailed information about size and crystallographic orientation of crystals forming the eggshell. This information can be automatically extracted using specially designed software. 5. Access to the software is available on a website, the address of which is given in the Materials and Methods section. 6. In this paper, specific examples of how these analyses are applied are set out and recommendations for obtaining different types of microstructure information are given. In addition, the limitations of the technique are discussed.