Equivalence of HPLC and colorimetric assay for purine derivatives and creatinine in Cattle urine

Traditional colorimetric methods for the assay of allantoin, uric acid and creatinine in cattle urine was compared with a reversed phase high performance liquid chromatographic method for the simultaneous determination of purine derivatives (PD) and creatinine in ruminant urine. Twenty cattle urine samples were analyzed by both the techniques. Intraclass correlation was estimated for assessing agreement and consistency between the two methods. The lower limit of the 95% confidence interval of the intraclass correlation obtained in this study was greater than 0.84. Moreover, the mean values estimated by both the methods were similar (P>0.66) and the methods did not exhibit marked systematic bias. The study concluded that both the methods could be used interchangeably for the assay of PD and creatinine in cattle urine.