Phosphorus requirements of poultry. IV. The effects on growing pullets of feeding diets containing no animal protein or supplementary phosphorus

Pullets reared to 18 weeks of age on diets containing no animal protein supplements and to which no source of inorganic phosphorus was added showed no clinical symptoms of rickets and no significant differences in average body weight, feed consumption, efficiency of feed conversion or livability compared with pullets reared on comparable diets supplemented with inorganic phosphorus.

The results indicate that growing pullets are able to use effectively organic sources of dietary phosphorus for growth and bone formation and can be reared satisfactorily on starter diets containing lower levels of total phosphorus than currently recommended.

Replacing protein of animal origin in pullet starter and growers' diets by soyabean meal and DL‐methionine or by extracted soyabean meal and extracted sunflower seed meal did not result in any adverse effects.