• glomerular filtration rate
• iohexol
• seagull

Endogenous markers commonly used in veterinary medicine to detect kidney disease in its early stages are not quantifiable in avian species. Consequently, it is necessary to explore alternative markers that are sufficiently sensitive, reliable, and compatible with clinical practice. The objective is to investigate the accuracy of limited sampling models for estimating the glomerular filtration rate (GFR) in adult yellow-legged gulls (Larus Michahellis) using the plasma clearance of iohexol.
The GFR estimated from the plasma concentration of iohexol at 3 sampling times, known as limited sampling models, was compared with that estimated from the reference model at 6 sampling times conducted at 5, 15, 30, 60, 90, and 180 minutes after the injection of the marker. The mean ± SD of the GFR for the reference model was 6.88 ± 2.46 mL/min/kg and did not significantly differ from the GFR estimated by the limited sampling models. Model 4, in which GFR was estimated using plasma IOX concentrations at 5, 15, and 90 minutes after iohexol administration, showed the least bias in GFR estimation compared to the reference model.
The findings revealed that iohexol plasma clearance through limited sampling models represents a reliable, accurate, and clinically applicable method for calculating GFR in gulls. This strategy could contribute to the validation and subsequent development of clinical renal biomarkers.