Magnesium Deficiency in the Duck

Abstract

The magnesium requirement of the duckling for maximum rate of growth during the first 16 days post-hatching is met when the diet contains 50 mg of magnesium per 100 gm. The manifestations of a magnesium deficiency are retarded growth, incoordination, convulsive attacks and death. With 20 mg of magnesium per 100 gm of diet, the only gross symptom was retardation of growth. The alkaline phosphatase activity of the brain of ducklings with magnesium deficiency was significantly lower than for the controls. The diphosphopyridine nucleotidase in the brain of birds fed the magnesium-deficient diet was significantly lower after 16 days than for the controls. The inorganic pyrophosphatase and cytochrome oxidase activities were not affected by feeding a diet low in magnesium. The niacin, riboflavin and pantothenic acid levels of the liver were not affected by feeding a diet deficient in magnesium. The average liver values expressed per 100 gm of fresh tissue were: niacin 12.7 mg, riboflavin 2.6 mg and pantothenic acid 3.1 mg. Of the total pantothenic acid, an average of 2.5 mg per 100 gm liver occurred in the bound form, presumably as coenzyme A.