Revista Facultad Nacional de Agronomía, Medellín
Print version ISSN 0304-2847
ESCOBAR PUERTA, Libardo; BOLIVAR VERGARA, Diana María and ESPINOZA GARCIA, Diana. USE OF THE CREATININE EXCRETION AS ALTERNATIVE METHOD TO TOTAL URINE COLLECTION IN HOLSTEIN COWS. Rev.Fac.Nal.Agr.Medellín [online]. 2010, vol.63, n.2, pp. 5567-5576. ISSN 0304-2847.
The research in animal production requires the total harvesting of tinkles to estimate the excretion of nitrogenated compounds and puric derivates, which brings great difficulties, doing necessary the search of alternating techniques. The objective of this work was to determine the volume of tinkles of Holstein cows by collects total with harness and the gathering samples spot using the excretion creatinine like internal marker and evaluate the variation in daily creatinine excretion using collections for seven days. A paired test (5% probability) was used to compare observed (total collection) and estimated (samples spot) urine volumes. Number of sampling days was compared by mixed model with repeated measures over time, the same animal (random effect) and day (fixed effects). Also was used the MIXED procedure and REPEATED command (SAS, 2001). The correlation between observed and estimated urine volume was performed by PROC CORR and regression was performed by PROC REG (SAS, 2001). The creatinine excretion average was 29.89 mg/kg of BW. It was not difference between the two techniques. The urine volume obtained was 19.8 L and the estimated urine volume was 19.7 L. There was a high correlation between the two techniques (r=0.82; P<0.001). Urinary excretion of creatinine was not affected by the number of urinary collection days. It was concluded that spot samples of urine, is a good estimator of the urinary volume and 24 hours of urine collection were required to accurate determine creatinine excretion
Keywords : Nutrition; ruminants; samples spot; urinary volume.