In vitro Study on the Mechanism of Ammonium Chloride on the Prevention of Urolithiasis in Fattening Cattle

Abstract

The mechanism of ammonium chloride on the prevention of urolithiasis in fattening cattle was examined in vitro through the solubility of magnesium phosphate and magnesium ammonium phosphate in tris-maleate buffer solution. Tw ograms of magnesium phosphate or magnesium ammonium phosphate were added to 300ml aliquots of were shaken on a mechanical shaker for 6 hours. Samples of 5ml were taken from each flask at intervals of 0, 1, 2, 4 and 6 hours after shaking.When pH values were decreased in buffer solutions, the solubilities of magnesium phosphate and magnesium ammonium phosphate clearly elevated. Phosphorus concentrations in supernatant liquids tended to be decreased by increasing the calcium concentration in aliquots of buffer solution. It was considered that this result was due to the formation of the complex of calcium and phosphorus.Only slight increases in the solubilities of magnesiu phosphate and magnesium ammonium phosphate were induced by adding sodium salts. In the range from 0 to 200mg%, and 0 to 600mg%, the solubilities of magnesium phosphate and magnesium ammonium phosphate tended to decrease while the concentratio of ammonium increased. It was suggested from these results that, among the effects of ammonium chloride, the decreasing of urine pH would play the most important role on the prevention of urolithiasis in fattening cattle.