Gas concentrations during storage do not affect hatchability and chick quality

Egg storage longer than 7 d is associated with a delay in hatch time, and a decline in hatchability and chick quality. During egg storage, embryo viability declines due to an increase in cell death. Albumen quality, which affects the micro environment of the embryo, declines as well due to a rise in albumen pH and a decline in albumen viscosity. Whether the change in albumen quality affects embryo viability is unknown. An experiment was conducted to investigate the effect of high CO2 concentrations or high N2 concentration during storage on albumen quality, hatchability and chick quality. A high CO2 concentration reduces CO2 loss from the egg and therefore maintains albumen quality. A high N2 concentration reduces the availability of oxygen. Eggs were stored for 14 d in 4 different storage conditions: normal air (control), 0.75% CO2, 1.5% CO2, and 95.8% N2. Storage temperature was 16°C and relative humidity was 75%. During incubation, eggshell temperature was maintained at 37.8°C, relative humidity varied between 45-60%, and carbon dioxide level was held below 0.35%. Albumen quality was measured at oviposition and at the end of storage. Hatchability of fertile eggs was calculated and chick quality was measured 12 h after the chick emerged from the eggshell. At the end of storage, the control and N2 groups had a higher albumen pH (9.43 and 9.59, respectively) than the 0.75% and 1.5% CO2 groups (8.70 and 8.48, respectively; P