Small Egg Diameter as a Selection Criterion of Broilers

Abstract

The shape of the egg is directly related to the productive and reproductive qualities of broilers. Large and small egg diameters are characterized by low variability (Сvbd = 4.74%, Сvmd = 2.73%). However, the range of variability of these characters was 9 and 10 mm, respectively; and 64.12% and 75.16%, respectively, of the layers according to these characters are outside the modal classes. The most informative is the small diameter of the egg. The correlation coefficient of the small diameter of the egg with live weight at 28 days of life is 0.734 (P <0.01), with hatchability of 0.270 (P <0.05). In addition, the small diameter of the egg has a significant negative relationship with mortality of embryos during the incubation period. The proportion of genotypic variation in the small diameter of an egg in both fathers and mothers is two times greater than that of a large diameter. Consequently, the small diameter of the egg, which, as a sign of chicken selection, can be another breeding trait increasing the offspring's live weight and reproductive qualities.