The Effect of High CO2 Atmosphere on the Laying Hen

Abstract

HALL and Helbacka (1959) demonstrated that feeding NH4Cl to laying hens increased the albumen height and reduced shell thickness during the feeding period. Hunt and Aitken (1962) confirmed this report and suggested that plasma bicarbonate was depressed during feeding of NH4Cl causing thinner shells. The present preliminary study was conducted to determine if changing the acid base balance via the respiratory system would have the same effect as feeding NH4Cl. Trial 1. Four Hy-Line laying hens were kept in an enclosed plastic covered chamber of approximately 6.5 cu. ft. to which a 5% CO2 and 95% gas mixture was metered at 4 liter/min. for a 19-hour period. The birds were returned to a normal gas environment for seven days, then exposed again for a 54-hour period to the same gas mixture. The temperature remained 21°C.±2° and excess moisture was removed with H2SO4. The chamber resembled a closed system. The…