The effects of diet supplemented with sodium bicarbonate upon blood pH, blood gases and eggshell quality in laying geese

The effects of diet supplemented with sodium bicarbonate (NaHCO3) upon blood pH, blood gases and eggshell quality during the laying cycle in geese were investigated. Fourteen geese aged 2 yr old were divided into two groups as; control (Group C, n = 7) and 0.5% NaHCO3 -supplemented group (Group T, n = 7). After 15 days of adaptation period, blood samples were collected every 6 h during a single laying cycle (over 42 h) and the data obtained were analysed for the pH, base excess (BE-B), HCO3- concentration, partial CO2 pressure (pCO2) and total CO2 concentration (tCO2). The parameters of eggshell quality (i.e. thickness and weight) were also measured following the laying. No correlation was found between the groups for the same blood parameters measured. But, there was a significant correlation (min. r = 0.946 and P < 0.05) between all the parameters except for the pH in the groups. Following NaHCO3 supplementation of diet however, there was no significant improvement in eggshell thickness and weight. These findings indicate that the NaHCO3 supplementation of diet may support the maintenance of venous blood pH, BE-B, HCO3-, pCO2 and tCO2 levels at the physiological ranges which are required for normal health and production status of goose during the laying cycle.