The influence of dietary phosphorus level on laying hen performance, egg shell quality, and various blood parameters

The influence of dietary phosphorus on hen performance and egg shell quality was investigated. Total dietary phosphorus levels of .17, .23, .30, .40, .50, .70, 1.50, and 2.30% were fed to four body weight groups of 23-week-old White Leghorn hens. Hens consuming the diets containing .17, .23, and .30% phosphorus, all from plant origin, consumed significantly (P less than or equal to .05) less feed, which resulted in poorer performance than hens fed diets supplemented with inorganic phosphorus. Addition of supplemental inorganic phosphorus at levels of .10 to .40% resulted in the best overall hen performance. Plasma phosphorus was directly related to dietary phosphorus level. Egg shell quality as measured by specific gravity was inversely related to dietary phosphorus levels above .50%.