Influence of feeding a high calcium diet for various durations in prelaying period on growth and subsequent performance of White Leghorn pullets.

An experiment was conducted to determine the effect on growth and subsequent performance of feeding a diet containing a high level of calcium to pullets for various durations in the late part of the growing period. The control group was fed a diet containing .8% calcium from 14 to 20 wk of age. Other groups were fed a diet containing 3.5% calcium from 18, 17, 16, 15, or 14 wk of age until reaching 20 wk of age. Available and total phosphorus content of control and high calcium diets were equal (.4 and .61%, respectively). From 20 to 60 wk of age all groups were fed a laying diet containing 3.55% calcium and .42% available phosphorus (.61% total phosphorus). The high calcium diet did not have significant adverse effects on weight gain, feed consumption, or mortality in the growing period. Kidney weight, liver, fat, and plasma level of uric acid were not significantly different for birds fed the high calcium diet for various durations as compared with birds in the control group. Tibia ash and tibia calcium were consistently higher for birds fed a high calcium diet for 2 wk or longer during the growing period. Sexual maturity was advanced due to feeding a high calcium diet in the growing period. Feeding a high calcium diet for various durations in the growing period did not have any adverse effects on production traits during the laying period.