Renal clearance, urinary excretion of endogenous substances, and urinary diagnostic indices in healthy neonatal foals.

The research article conducts a study on the urinary system of healthy neonatal foals (pony or horse) examining the renal clearance, the excretion of endogenous substances in urine, and urinary diagnostic indices. This information is critical in determining the healthy and proper functioning of the kidney in these newborn animals.

Methodology

The researchers carried out their study by collecting serum (S) and urine (U) samples every two hours from eight healthy 96-hour-old foals. Simultaneously, samples of the dams’ milk were also obtained. The volume of urine produced during this period (12 or 24 hours) was measured and the average amount was calculated to be 148 +/- 20 ml/kg/day.

Baseline Evaluation

• Urinalyses of all foals were performed at the age of two days, prior to any manipulation.
• The urine was generally found to be dilute (with a specific gravity less than 1.008), but in one case of a healthy foal, the specific gravity was as high as 1.027.

Effects of Catheterization

• Continual catheterization for 12 or 24 hours resulted in bacteriuria, indicating the presence of bacteria in the urine. However, there were no white blood cells found in the urine.
• The prolonged catheterization did not induce fever or any symptoms of cystitis or other illnesses in the foals.

Urinary Electrolyte Profile

• The excretion and clearance of urinary electrolytes and fractional electrolyte excretions (FE) were also recorded.
• The data was compared with standard values reported in adult horses. The excretion, clearance, and FE are similar for sodium (Na), but they are higher for other elements like potassium (K), phosphorous (P), and calcium (Ca).

Conclusion

Upon comparing the collected data during different time periods, the researchers found no significant differences. It was thus concluded that using a single sample estimate of urine/serum fractional excretion is an accurate way to determine the handling of electrolytes by the kidney in neonatal foals. Furthermore, when combined with a urinalysis and other serum parameters, it can provide invaluable information about renal function.