The Effects of Heredity and of Certain Environmental Factors on the Incidence of Blood Spots in Chicken Eggs

Abstract

THE problem of blood spots in chicken eggs has been receiving attention recently. Quinn and Godfrey (1940) and Nalbandov and Card (1941) have indicated that there is an hereditary basis for the occurrence of blood spots. Lerner and Smith (1942) state that both seasonal and hereditary differences between birds contribute to the variation in the incidence of blood spots. The data presented in this paper confirm that heredity is of major importance in the incidence of blood spots and at the same time the importance of several environmental factors is considered. MATERIALS AND METHODS A 10-egg sample, collected between May 27 and June 29, 1942, from each of 238 Single Comb White Leghorn pullets was available for study. The 238 pullets came from 22 dams and 6 sires, and, of the total number of pullets, 110 were located in individual laying cages and 128 kept under ordinary floor conditions. The . . .