Three experiments involving a total of 550 laying hens were conducted to study the effects of low level lactose feeding on the egg production characteristics of laying hens. The specific purposes were to determine if lactose influenced calcium utilization and feed intake and if there were any important interactions between lactose and calcium. There was a consistent significant improvement in egg shell breaking strength as a result of lactose supplementation. One percent dietary lactose appeared to be adequate to achieve this improvement. The addition of 2 or 3% lactose did not result in any greater improvement than 1%. There were no consistent influences of lactose, lactose source, or calcium level on feed intake or any of the other variables examined in the three experiments. As was expected, 61-week-old hens laid significantly fewer and larger eggs with weaker shells than 47-week-old hens. There were four statistically significant interaction effects: lactose level X calcium level on egg production; lactose level X calcium level on egg shell strength; and age X lactose level on egg shell strength. Even though these effects were statistically significant, it is questionable whether or not they are of practical importance in feeding laying hens.
Animals Calcium, Dietary