Strain Differences in Egg Shell Mottling, Internal Quality, Shell Thickness, Specific Gravity, and the Interrelationships Between These Factors

THE basic purpose of this experiment was to find out more about egg shell mottling; its inheritance, and its relationship to other characteristics of the egg. Egg shell mottling is described by Baker and Curtiss (1957) as light-colored, translucent spots of various sizes and shapes appearing in the shell under candling Holst, Almquist and Lorenz (1932) state that shell mottling is caused by moisture distributed in a non-uniform manner throughout the shell proper. They point out that egg shell mottling is not a permanent characteristic and can vary in amount after the egg is laid. The mottling of the shell is not affected by the porosity of the shell according to Almquist (1933). Jeffrey and Darago (1940) point out that high relative humidities reduce the amount of egg shell mottling. They also state that the incidence of shell mottling is greatest at low relative humidities. Baker and Curtiss (1957) state . . .