Plasma CO2 Capacity of Laying Hens

HALL and Helbacka (1959) reported that during feeding of NH4Cl shell thickness dropped along with a drop in blood pH. This would indicate that the laying hens were suffering from acidosis which may account for the thin shells. Dyer and Roe (1934) reported values of 42 volumes percent for CO2 combining power of chicken plasma. Altman and Dittmer (1961) gave the average CO2 capacity of chicken plasma as 51.2 volumes percent with a range from 46.7–57.9 volumes percent. Measurement of plasma CO2 capacity will give an indication of the acid-base status of the blood. Therefore, a study was conducted to determine if a relationship existed between plasma CO2 capacity and egg quality factors. Sixty Hy-Line laying pullets were selected for this study and kept in cages. Records were kept of egg production, egg weight, Haugh units, and shell thickness from December through August. Feed was not removed from…