Method for improving egg‐shell strength by selection12

Abstract
A method was developed for measuring the rate of egg breakage under random impact loading of samples from sire families [white Leghorn chickens]. Bidirectional selection based upon sire family means, was made over a single generation using egg breakage rate as the basis of selection; significant differences were obtained after 1 generation. Heritability of the rate of egg breakage was estimated as 0.48 .+-. 0.05.