Table 2.

Determined parameters of the serum and urine.

	Healthy dogs					Dogs with CKD
	GS < 2 y. o.	GS 2–6 y. o.	GS > 6 y. o.	BS	SD	CKD1	CKD2
n	19	30	13	6	6	7	8
Crea (μmol/L) RI: 46–88	72.34 ± 15.54	83.67 ± 11.46	79.38 ± 15.13	81.83 ± 16.17	59.48 ± 11.06	102.96 ± 22.38	127.75 ± 17.88
Urea (mmol/L) RI: 3.97–8.05	5.35 ± 1.64	5.99 ± 1.41	5.50 ± 2.12	5.88 ± 1.68	5.94 ± 1.07	6.76 ± 2.43	8.74 ± 1.67
SDMA (mg/dL) RI <14	9.00 ± 1.80	8.25 ± 1.99	8.92 ± 2.15	7.67 ± 3.08	8.00 ± 1.79	8.57 ± 4.58	12.50 ± 6.00
P (mmol/L) RI: 0.9–1.91	1.95 ± 0.49	1.29 ± 0.17	1.19 ± 0.15	1.15 ± 0.47	1.51 ± 0.20	1.37 ± 0.16	1.31 ± 0.16
UCrea (mmol/L)	18.44 ± 8.98	19.45 ± 7.43	12.35 ± 7.25	18.48 ± 6.90	17.00 ± 4.89	20.04 ± 11.69	22.59 ± 6.90
UrKl (pg/mL)	198.43 ± 42.58	185.72 ± 54.85	207.13 ± 35.39	162.76 ± 34.81	191.92 ± 38.10	185.49 ± 28.82	199.13 ± 58.50
UrKl/Cr (pg/gCr)	12.66 ± 8.43	9.66 ± 4.28	21.21 ± 15.43	8.78 ± 3.45	10.75 ± 3.59	13.61 ± 14.09	8.46 ± 3.31

GS, German shepherds; BS, Belgian shepherds; SD, small breed dogs; y. o., years old; CKD1, chronic kidney disease stage 1; CKD2, chronic kidney disease stage 2; Crea, serum creatinine; SDMA, symmetric dimethyl arginine; UCrea, urinary creatinine; UrKl, urinary soluble alpha klotho; UrKl/Cr, urinary alpha klotho to creatinine ratio; RI, reference interval. Data are presented as mean ± SD.