IN THE rather extensive literature relating to the effects of fluorine on the animal body, there is no reference, so far as we know, to the effect of feeding fluorides to chickens. However, certain experiments with the use of rock phosphate containing fluorides as a mineral supplement for chickens have a bearing on this problem, and will be referred to in connection with our experiments.

Summary

Chicks of various ages were fed sodium fluoride in amounts ranging from 0.015 to 1.2 percent of the ration.

No unfavorable effect on the appearance or weight of the chicks was noted with levels up to 0.15 percent of sodium fluoride.

The 0.3 percent level of sodium fluoride depressed appetite and the weight of young chicks, but had little effect on chicks two and three months old. Sodium fluoride at a 1.2 percent level proved markedly toxic to chicks of all ages.

The ingestion of 0.6 percent and 1.2 percent of sodium fluoride resulted in an apparent lowering of serum calcium in the young chicks. There was no evidence of any effect of sodium fluoride on the serum calcium The ingestion of 0.6 percent and 1.2 percent of sodium fluoride resulted in an apparent lowering of serum calcium in the young chicks. There was no evidence of any effect of sodium fluoride on the serum calcium or inorganic phosphorus of older chicks.

No consistent effect of sodium fluoride on bone ash was observed within the limits of these experiments.

Sodium fluoride ingestion did not have any significant effect on the kidney phosphatase of chicks.

No evidence was obtained that fluorine feeding influences either the size or the structure of parathyroids.

Small hemorrhages were observed in the duodenal loop of some of the fluorine fed chickens at all levels of fluorine intake.

The ingestion of 0.96 percent of sodium fluoride caused depression of weight and marked decrease in egg production of hens.