The Gaseous Environment of the Chick Embryo in Relation to Its Development and Hatchability

Abstract

EXPERIMENTS exposing hatching eggs from the 193rd through the 288th hrs. of incubation were conducted in continuation of a program of testing the effect of various CO2 and O2 levels upon embryonic development and hatchability. Previous reports (Taylor et al., 1956; Taylor and Kreutziger, 1965) have dealt with results from two earlier periods of such treatments. While optimum gaseous conditions for hatching have been discussed in the literature (Romanoff, 1930; Barott, 1937; Ells and Morris, 1947; Wilgus and Sadler, 1954), the sensitivity of the embryo to changes in its gaseous environment during different stages of development has received little attention. Riddle (1924) has suggested that young embryos are more sensitive to high O2 and older embryos are more sensitive to low O2. An increasing tolerance to high CO2 during the second half of the incubation period is indicated by evidence presented by Barott (1937) and Sadler et al. (1954). As …