The effect of broiler breeder flock age and length of egg storage on egg albumen during early incubation.

The objective of these two experiments was to determine the temporal changes in albumen during storage and early incubation as a means of understanding some of the effects of egg storage on early embryonic development. Eggs from 30- or 50-wk-old broiler breeder hens were incubated (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 weight 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 greater in fresh eggs than in stored eggs in Experiment 1. Fresh eggs had significantly greater albumen height and significantly lower albumen pH than stored eggs in both experiments. These differences diminished with length of incubation. Because the blastoderm is located adjacent to the albumen, changes in the viscosity or pH of the albumen may play 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 trans-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.