An injectable composition when used for the treatment of a microbial infection in a mammary gland of an animal, wherein the composition includes a) a non-steroidal anti-inflammatory drug (NSAID)； b) an antibiotic selected from the group consisting of a beta lactam antibiotic and macrolide antibiotic； characterised in that the composition includes a non-aqueous solvent, and the NSAID and antibiotic in the composition are dissolved in the non-aqueous solvent.
