Effects of low-dose dexamethasone and prednisolone long term administration in beef calf: Chemical and morphological investigation Original Research Article

An analytical, pharmacokinetic and histopathologic investigation was conducted by two experimental trials on beef cattle in order to determine fate and effects of dexamethasone and prednisolone, administered to distinct cattle groups at low dosage for long periods of time. In trial 1, eighteen Charolaise beef cattle, male, 17–22-months-old, were divided in three groups: to group A (n = 6) dexamethasone-21-sodium-phosphate 0.7 mg day−1 per os for 40 days was administered; group B (n = 6) was orally treated with prednisolone 15 mg day−1 for 30 days, while group C (n = 6) served as negative control. Urine was collected at days 0, 7, 15, 25 and 47 from groups A and C, and at days 0, 8, 18 and 42 from group B. In trial 2, sixteen Friesian cattle, male, 10–17-months-old, were randomly divided into two groups: group D (n = 8) was administered prednisolone 30 mg day−1 per os for 35 days, while group K (n = 8) served as control. In both trials, the animals were slaughtered after a 6-days drug withdrawal and thymus and livers were collected and properly stored until the analysis was performed.