Effect of Calcium and Phosphorus Levels on the Performance of Layers in Nigeria

The effect of four levels of dietary calcium and two levels of dietary phosphorus, fed to Harco layers in battery cages and on deep litter for a period of 48 weeks on tibia ash, percent calcium of tibia ash and the retention of calcium and phosphorus was investigated. Both percent tibia ash and percent calcium content of tibia ash increased significantly (P<0.05 as the calcium content in the diet was increased from 2.00 to 4.25%. Birds housed on deep litter had significantly (P<0.01) higher tibia calcium than those housed in battery cages. Tibia ash and calcium content increased rapidly in the first eight weeks in production and thereafter remained fairly steady. Percent calcium retention decreased while absolute calcium retention increased with increasing level of dietary calcium. High dietary calcium level (4.25%) was accompanied by low percent and absolute phosphorus retention.