Physical characteristics of intact and cracked eggs

Six egg samples, comprising equal numbers of intact and cracked eggs, were collected from three flocks of hybrid layers. 2. Cracks were classified according to type (hole, star or straight) and the weight, shape, shell colour and specific gravity of all the eggs were measured. Shell thickness and dry shell weight were also recorded for a maximum of 10 intact and 10 cracked eggs from each sample. 3. The largest proportion of cracks were holes. 4. Differences in mean egg weight and shape of intact and cracked eggs within each sample were inconsistent. Mean shell colour was darker for the intact brown eggs than for the cracked ones. For all the samples, mean egg specific gravity, shell thickness and dry shell weight were higher for the intact eggs. The difference in egg specific gravity was significant (P<0.05) for all samples. 5. Holes occurred in eggs of lower mean weight but with better quality shells than those in which star or straight cracks occurred.