Four experiments involving CO2 level in single-stage incubators were conducted at a commercial turkey hatchery. Carbon dioxide was injected into incubators to a level of .3% during the first 10 days of incubation. Noninjected control incubators were maintained at a .1% CO2. Eggs from the injected incubators had a higher hatchability and lower early, late, and malpositioned embryonic mortality. No difference in hatchability was found between .3 and .5% CO2 concentrations for the first 10 days of incubation. Carbon dioxide injection for the first 5 days of incubation decreased hatchability when compared to CO2 injection for the first 10 days. Carbon dioxide injection for the first 14 days of incubation resulted in no difference in hatchability from injection for the first 10 days. The artificial addition of CO2 to single-stage turkey incubation systems may be of economic importance in commercial hatcheries because of its effect on hatchability.
