Pharmacokinetic and urinary profiling reveals the prednisolone/cortisol ratio as a valid biomarker for prednisolone administration

Table 3 Urinary prednisolone, prednisone, 20α-dihydroprednisolone and 20β-dihydroprednisolone concentrations during growth-promoting and therapeutic prednisolone treatment

	Prednisolone	Prednisone	20α-dihydroprednisolone	20β-dihydroprednisolone
A1. Oral growth-promoting treatment
N° positive	12	0	8	12
C_min (μg L⁻¹)	0.027	-	0.153	0.695
C_max (μg L⁻¹)	1.17	-	3.41	14.10
Mean (μg L⁻¹)	0.832	-	0.771	4.35
SD (μg L⁻¹)	0.381	-	0.544	2.44
A2. Intramuscular growth-promoting treatment
N° positive	12	4	8	12
C_min (μg L⁻¹)	0.014	0.030	0.138	0.938
C_max (μg L⁻¹)	8.44	2.17	1.79	14.2
Mean (μg L⁻¹)	1.16	0.311	0.472	4.91
SD (μg L⁻¹)	1.08	0.413	0.308	3.15
B1. Oral therapeutic treatment
N° positive	12	2	8	12
C_min (μg L⁻¹)	0.038	0.033	0.156	1.07
C_max (μg L⁻¹)	1.36	0.306	2.85	15.15
Mean (μg L⁻¹)	0.922	0.125	0.552	5.13
SD (μg L⁻¹)	0.428	0.108	0.635	1.20
B2. Intramuscular therapeutic treatment
N° positive	12	12	12	12
C_min (μg L⁻¹)	0.528	1.08	3.32	8.97
C_max (μg L⁻¹)	189	22.5	127	100
Mean (μg L⁻¹)	31.3	8.17	14.9	37.9
SD (μg L⁻¹)	40.7	5.91	26.0	25.0

For each of the treatment set-ups (A1, A2, B1, B2), 12 bovines were considered. In case that a glucocorticoid was not found in the urine samples of all animals, means ± SD were determined based on the positive urine samples only

ISSN: 1746-6148