Summary Day-old Japanese quail fed a zinc-low purified diet containing soybean protein were severely deficient at 4 weeks of age. The zinc deficiency was characterized by slow growth, abnormal feathering, labored respiration, an incoordinate gait, low ash content of the tibias and low concentrations of zinc in the livers and tibias. Control birds fed the same diet supplemented with zinc grew and developed normally. Successful use of the Japanese quail in this study indicates that the animal has great potential usefulness for nutrition studies.