Prednisolone and prednisone neo-formation in bovine urine after sampling

Area of Science:

• Veterinary Pharmacology
• Analytical Chemistry
• Food Safety

Background:

• Increased detection of prednisolone in bovine urine samples from Northern Italy raises concerns.
• Potential for neo-formation of prednisolone or prednisone in urine post-collection requires investigation.
• Ensuring accurate drug residue analysis is crucial for animal health and food safety compliance.

Purpose of the Study:

• To investigate the potential neo-formation of prednisolone and prednisone in bovine urine.
• To assess the impact of storage temperature, fecal contamination, and deconjugation on prednisolone levels.
• To determine the reliability of prednisolone detection in routine bovine urine analysis.

Main Methods:

• Analysis of cow urine samples using High-Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS3).
• Incubation of urine samples at 37°C with and without fecal contamination over 24 hours.
• Investigation of Helix pomatia juice influence on corticosteroid deconjugation.

Main Results:

• Inappropriate storage temperatures and fecal contamination significantly increased prednisolone concentrations in some samples.
• Neo-formation of prednisolone was observed under specific conditions, potentially leading to false non-compliance accusations.
• Helix pomatia juice did not significantly alter prednisolone levels, suggesting its presence in free form.

Conclusions:

• Improper sample handling (temperature, contamination) can lead to erroneous prednisolone detection in bovine urine.
• The study highlights the importance of strict sample collection and storage protocols to ensure analytical accuracy.
• Findings underscore the need for careful interpretation of prednisolone results in routine veterinary controls.