Response of Brown-Egg Strain Layers to Dietary Calcium or Phosphorus

Two experiments were conducted to observe brown-egg layer response to dietary calcium or phosphorus. In one experiment, birds were fed experimental diets providing .4, .35, .3, or .25% available phosphorus at 3.5% calcium, from 19 to 71 wk of age. Diet had few significant effects on performance characteristics. The two extreme levels of available phosphorus resulted in reduced (P < .01) eggshell quality as assessed by shell deformation. In a second study, 19-wk-old pullets were fed diets providing 2.8, 3.4, 3.8, or 4.2% calcium, at .4% available phosphorus to 71 wk of age. Diet had no effect on egg production, egg size, feed intake, body weight, or eggshell quality (P > .05). It seems that the brown-egg layer requires no more than 3.4 g calcium/day and that the available phosphorus requirement is met with daily intake of 358 mg.