The influence of saline drinking water on the activity of carbonic anhydrase in the shell gland of laying hens

Abstract

Carbonic anhydrase activity was measured in three experiments using mucosal extracts from the shell gland of laying hens given drinking water consisting of town water with or without the addition of sodium chloride (2 g/l). Hens laying eggs with normal or defective shells on both treatments were used. The specific activity of carbonic anhydrase was significantly lower in hens receiving the saline drinking water, but egg shell type had no significant effect on enzyme activity. The results indicate that a reduced activity of carbonic anhydrase in the shell gland contributes to the poor egg shell quality observed in hens receiving saline drinking water.