| Popis: |
INTRODUCTION A REVIEW of the literature dealing with the effect of size of the particle of grit for poultry reveals very little work done on this phase of mineral nutrition. Workers at the Iowa Experiment Station (1927) compared powdered limestone with limestone grit. They reported that “in the case where fine powdered limestone was fed, fewer eggs were laid than where it was given in a larger size.” Halpin and Hayes (1926) reported that tests of pulverized oyster shell were made. These workers reported egg production consistently lower in the pens receiving this material than in those where coarse crushed oyster shell was fed. Tepper, Durgin, and Bottorff (1939), in summarizing a study of fine and coarse grit, drew three conclusions that are of interest in this study. These are: 1. Fine granite waste is not detrimental to chick growth during the initial 16-week period; but its detrimental effects are . . . |
