Effect of supplemental dietary minerals on production, physiological paramenters, and the use of iron as a resting diet for caged layers

Abstract

Two hundred and sixteen hens were divided into six treatment groups, each consisting of three replicates of twelve Single Comb White Leghorn hens, housed two birds per cage, in a study to determine the effects of dietary mineral supplements on egg production, egg characteristics, and certain physiological parameters. Hens were fed a basal practical diet consisting of 16.3% protein, 3.1% calcium and .73% phosphorous. The basal diet was supplemented with either 0, 25, 50, 100, 200, or 400 ppm of Fe in the form of reagent grade ferrous sulfate (FeSO₄x7H₂O) for twelve 28-day periods. Feeding diets with iron supplements as high as 400 ppm resulted in no statistically significant differences in percent hen-day production, egg weight, percent shell, or shell thickness. Hemoglobin and hematocrit values were not significantly affected by the increase in dietary iron. Egg yolks from control and the 400 ppm Fe group did not differ significantly in their iron content. ...