THE EFFECT OF BROILER BREEDER FLOCK AGE AND LENGTH OF EGG STORAGE ON EGG-ALBUMIN DURING EARLY INCUBATION

The objective of these two experiments was to determine the temporal c hanges in albumen during storage and early incubation as a means of un derstanding some of the effects of egg storage on early embryonic deve lopment. Eggs from 30- or 50-wk-old broiler breeder hens were incubate d (37.5 C dry bulb, 30 C wet bulb) after storage for 0 (fresh) or 5 d (18 C, 75% RH) in Experiment 1. Albumen height, albumen pH, and egg we ight loss were recorded at 2, 24, 48, and 66 h of incubation. The same measurements were taken on another group of eggs from 43-wk-old hens stored for 0 (fresh), 4, 8, or 12 d in Experiment 2. All hens were of the same strain. Egg weight loss during incubation was significantly g reater in fresh eggs than in stored eggs in Experiment 1. Fresh eggs h ad significantly greater albumen height and significantly lower albume n pH than stored eggs in both experiments. These differences diminishe d with length of incubation. Because the blastoderm is located adjacen t to the albumen, changes in the viscosity or pH of the albumen may pl ay an integral role in determining the viability of the embryo during the very early stages of development. Incubation of fresh eggs without storage appears to expose the developing embryo to an inappropriate t rans-vitelline membrane pH gradient and a thick albumen that may slow vital gas diffusion and limit nutrient availability. These conditions may cause an increased incidence of embryonic death.