The use of specific gravity of the egg to estimate shell thickness

Errors of the order of 10 μm could be introduced if specific gravity (SG) was used to estimate shell thickness when the comparison was being made between eggs from hens of different breeds or of different ages. 2. The precision of estimates made on the basis of SG measurements on eggs from within a flock of hens of uniform breed and age could be significantly improved by the use of egg weight information.