External Bone Volume, Ash, and Fat-Free Dry Weight of Femurs of Laying Hens Fed Diets Deficient or Adequate in Phosphorus

The femurs of laying hens fed diets containing .18, .23, or .43% available phosphorus were evaluated. External bone volume (V) and organic matter (OM) content and OM/V were not different. Ash (A), percent bone ash, and A/V were significantly less at the two lowest levels of dietary phosphorus. It was concluded that the femurs of phosphorus deficient laying hens have a reduction in mineral content but not organic matter, Determination of external bone V and expression of A/V may be of value in assessing osteoporotic bone.