RESPONSES IN EGG-SHELL QUALITY FROM DIETARY ASCORBIC-ACID SUPPLEMENTATION OF HENS RECEIVING SALINE DRINKING-WATER

Three experiments were conducted to determine whether the poor shell quality of eggs from hens receiving saline drinking water could be improved by the simultaneous addition of ascorbic acid to the diet. In one experiment, the responses were compared with those of hens receiving ascorbic acid in the drinking water. In this experiment, providing the ascorbic acid in the drinking water on a daily basis was compared with dosing the water on alternate days. The results showed that saline water increased the incidence of egg shell defects without affecting food and water intakes, egg production or egg weight. Changes in a range of shell quality measures mirrored the changes in the incidence of egg shell defects. Supplementation of the diet or drinking water with ascorbic acid prevented the increase in shell defects and the decrease in shell quality. The degree of response to dietary ascorbic acid was dependent on the concentration used, a response similar to that observed previously when the ascorbic acid was added to the drinking water.