Supplementation of broiler drinking water with liquid ammonium polyphosphate

1. In each of two experiments lasting 21 days a commercially available ammonium polyphosphate solution was provided in the drinking water as the sole source of supplemental phosphorus for day-old chicks housed in batteries. 2. In both experiments, similar daily phosphorus intakes either from dicalcium phosphate in the food or from ammonium polyphosphate in the drinking water supported equivalent responses in body weight gains. The same was true for the tibia ash results in experiment 2. 3. Liquid ammonium polyphosphate, while marketed for addition to diets, appears to be also very effective as a waterborne source of phosphorus for broilers.