The Interrelationships between Dietary Molybdenum, Copper, Sulfate, Femur Alkaline Phosphatase Activity and Growth of the Rat

Abstract

Feeding 600 ppm of molybdenum resulted in a significant (P < 0.01) depression of femur alkaline phosphatase activity and growth of the rat. This depression in activity occurred between 10 to 17 days of molybdenum feeding and was evident up to 8 weeks of molybdenum feeding. Added dietary inorganic sulfate alleviated the molybdenum-induced depression in enzyme activity and partially mitigated the growth depression, whereas added copper had no effect. Through controlled feed intake studies, it was established that the decrease in enzyme activity, induced by molybdenum-feeding, was the result of the growth depression and not the ingestion of molybdenum per se. Dietary molybdenum, 600 ppm, completely suppressed growth. Equivalent growth depression was achieved by restricting the basal ration fed to about 62% of that consumed by the molybdenum-fed animals. Thus, a reduction in the efficiency of feed utilization is one of the important consequences of molybdenosis in the rat. Whether this loss in efficiency is effected through faulty digestion or absorption of nutrients or through some other derangement in metabolism remains to be determined.