Observations on a Magnesium-fluoride Interrelationship in Chicks

Abstract

The addition of high levels of both magnesium and fluoride to either practical or semipurified diets complete in all known nutrients produced the following results in young chicks: (1) greater reduction in growth than with either magnesium or fluoride alone; (2) the development of a characteristic leg weakness; (3) decreased calcification of the bone. Increasing the calcium level in the diets from 1.0 to 1.5% reduced but did not prevent the magnesium-fluoride relationship. The growth reduction, leg weakness and reduced bone ash caused by high dietary magnesium and fluoride were obtained only when one-day-old chicks were fed the experimental diets; these results were not observed when chicks at two weeks of age were fed the same diets, nor could the interaction be shown in weanling rats. Plasma alkaline phosphatase activity in chicks was elevated about twofold by added fluoride regardless of the dietary magnesium or calcium levels. The level of alkaline phosphatase in the plasma decreased with age in all groups at approximately the same rate. Dietary magnesium or fluoride levels did not influence the conversion of 3-phosphoglycerate to phosphoenolpyruvate by muscle homogenates. 11 references, 4 tables.