Effect of feeding sodium bicarbonate and ammonium chloride on induced avian urolithiasis and kidney damage in chicks

Cockerels (40) divided into 4 groups of 10 each were offered either control diet having normal calcium and normal phosphorus (NCP), or high calcium and low phosphorus (HCLP) to induce urolithiasis, or HCLP along with 1% NaHCO, (HCLPBi) or HCLPBi with 1% NH₄Cl. The diets were fed from the age of 9 to 32 weeks. Gain in body weight was highest with NCP diet and differed (P<0.01) from HCLP diet, whereas, feed intake and feed efficiency were reduced in all the HCLP diets. Mean serum calcium, phosphorus were at par in all the diets. Calcium retention differed (P<0.01) in between control and HCLP diets. Phosphorus retention was significantly higher (P<0.01) in control diet than the HCLP diets. Body mass was at par in all the diets. Kidney asymmetry was more than 1.0 in all the diets. On histopathology all the 55 to 88 per cent kidneys of HCLP diets showed urate crystals as against none of the NCP diet. It was concluded that high calcium low phosphorus diets induced urolithiasis and caused kidney damage and dietary acidification with NH₄Cl dissolved preformed uroliths.