Relationship Between Breaking Strength and the Percent of Egg Shell

DIFFERENCES in the amount of shell of eggs due to differences in rations or management factors with reference to sunlight or irradiation have been reported by a number of investigators. Hughes, Payne, and Latshaw (1924 and 1925) found that the irradiation of hens confined without access to direct sunlight resulted in eggs with 44 percent heavier shells. Hart and co-workers (1925) report eggs with heavier shells and of higher calcium content as a result of irradiating hens confined without access to direct sunlight. Taylor and Martin (1928) found that confined hens which were irradiated and hens which had access to direct sunlight laid eggs which had a higher percent of shell than eggs produced by hens without either irradiation or sunlight. Morgan, Mitchell, and Roderick (1930) found a slight but measurable difference in the percent of egg shell due to the addition of cod liver oil to a standard ration . . .