Comparison of different eggshell thickness measurement methods

This study was conducted to examine how various methods affect the results of eggshell thickness measurements. Direct and indirect measurements were performed on 700 table eggs which were daily collected from the same flock. The shell thickness of the eggs was calculated according to a logarithm which uses egg weight. Eggs with a specific gravity of higher than 0.80 g/cm(3) were classified as thick-shelled, whereas the others were categorized as thin-shelled. After determining the shell thickness of the eggs by an ultrasound gauge, all of the eggs were broken, the shells were separated, and the shell thickness of each egg was measured with two micrometers (digital and manual). Values measured by the manual micrometer were considered as actual thicknesses. Lowest correlation was determined between the logarithm method and the others (P > 0.05). However, there was a significant correlation between ultrasound and micrometer measurements (P < 0.05). According to the results of the current study, ultrasound measurement may be accepted as a suitable method for determining the eggshell thickness without breaking the egg.