Metabolism study to determine the quantity and identify the nature of parent compounds and metabolites in ovine tissue and fluids following the topical administration of Tri-Solfen

Mulesing, tail docking, and castration are animal husbandry procedures conducted on farm as part of routine management. Tri-Solfen is used in Australian sheep industries for the provision of pain relief and to assist wound healing in lambs undergoing mulesing, tail docking, and castration. The data obtained from this study will allow better characterisation of residues in edible tissues and provide an understanding of the metabolism profiles of each of the three active ingredients in Tri-Solfen (lignocaine, bupivacaine and cetrimide), and provide supportive data for the definition of the withholding period (WHP) and export slaughter interval (ESI) for Tri-Solfen in lambs when applied topically. Results from this work have been provided to pharmaceutical companies for their use in applications to the APVMA.