Quantification of eggshell microstructure using X-ray micro computed tomography

Abstract

1. X-ray microcomputed tomography can be used to produce rapid, fully analysable, three-dimensional images of biological and other materials without the need for complex or tedious sample preparation and sectioning. We describe the use of this technique to visualise and analyse the microstructure of fragments of shell taken from three regions of chicken eggs (sharp pole, blunt pole and equatorial region).2. Two- and three-dimensional images and data were obtained at a resolution of 1.5 microns. The images were analysed to provide measurements of shell thickness, the spacial density of mammillary bodies, the frequency, shape, volume and effective diameter of individual pore spaces, and the intrinsic sponginess (proportion of non-X-ray dense material formed by vesicles) of the shell matrix. Measurements of these parameters were comparable with those derived by traditional methods and reported in the literature.3. The advantages of using this technology for the quantification of eggshell microstructural parameters and its potential application for commercial, research and other purposes are discussed.

Collection of the thinnest: A unique eggshell assemblage from the Late Cretaceous vertebrate locality of Iharkút (Hungary)

“…Similar MT III is indicated in mid-tangential sections (numbered white dashed lines) above and the corresponding radial serial sections are seen below. Note the different morphology and density of the pneumatic channel system with blindly ending cavities (short white arrowheads) and pores piercing through the entire eggshell thickness (white arrowheads) in the three different morphotypes blind canals have also been observed and described as "incomplete pore canals" in chicken eggshells (Riley et al 2014). In a few specimens, particular pores were surrounded by a pronounced, ring-like thickening on the inner surface of the eggshell (Fig.…”

“…11C, E). The eggshell has a very low density of pores (∼0.7/mm 2 ) and a somewhat higher density of blindly ending pneumatic cavities or incomplete canals (Riley et al 2014; ∼3.8/mm 2 ) as revealed by μCT investigation (Figs 6C and 7C). The individual pores run between the eggshell units; they are simple, straight, and column-like ( Fig.…”

Avian mitochondrial genomes retrieved from museum eggshell

“…through analysis of colour and shape; Beruldsen, Chapman & Macleod, ). These analyses can be achieved using various techniques including light and electron microscopy (Buss & Keiss, ; Oskam et al, ), computed tomography (Riley, Sturrock, Mooney, & Luck, ), reflectance spectrophotometry (Aviles, Soler, & Perez‐Contreras, ), Raman spectroscopy (Thomas et al, ) and mass spectrometry (Stewart, Allen, Jones, Penkman, & Collins, ).…”

Full Issue

“…Apparent inconsistencies in resin polymerization made replication of these earlier results difficult Tullet 1975, Bunk andCombs 1979). While other studies have used low-viscosity, epoxy-based resins (e.g., Spurr's resin; Tompa 1980), few reliable protocols and three-dimensional depictions of avian eggshell pores exist within the literature (but see Riley et al 2014). …”