Effects of High Dietary Calcium and Low Phosphorus on Urinary System of Broiler Chicks

The present study was carried out to investigate the effects of high dietary calcium and low phosphorus on urinary system of broiler chicks. A total of 90 (day-old) broiler chicks were divided into three equal groups A, B and C. The chicks were reared for 42 days on three experimental rations. Calcium:phosphorus ratio in the feed for groups A, B and C was maintained as 1:0.5 (control), 2:0.5 and 3:0.5, respectively. Various parameters studied included serum calcium and phosphorus concentrations, FCR, kidney:body weight ratio, and pathological examination of urinary system. The birds fed on high dietary calcium and low phosphorus revealed hypercalcaemia and hypophosphataemia in their sera. The FCR and mean kidney:body weight ratio of treatment groups was higher than the control group. The urinary system of the treated birds, in general, displayed inflammatory lesions, showing abnormalities of colour, size, shape and texture of kidneys and ureters. The ureters also showed occlusion and distention. The microscopic examination of the kidneys showing gross pathological lesions revealed common histopathological changes in glomeruli, tubular cells and interlobular veins.