The Effect of a Deficiency of Manganese in the Diet of the Hen

THE development of perosis in chicks is associated with, and perhaps results from, the depletion of certain organs, notably the bones, in manganese.3 Depletion was effected by feeding a diet deficient in manganese but containing all the other known dietary essentials. Perosis usually occurred in the chicks within three weeks after hatching, during a growth period which coincided with a period of low-manganese retention. The early development of perosis in some chicks less than 14 days of age suggested a possible manganese deficiency during the development of the embryo. The possibility of eggs being deficient in manganese as a result of a deficiency of manganese in the diet of the hen seemed reasonable, since Vecchi (1933) has reported that the manganese content of eggs is increased by feeding massive doses of MnCO3. In the present study, an attempt was made to produce eggs of low manganese content through alterations in . . .