Mercury completed its investment in Australian Animal Hospitals (AAH) in March 2015, acquiring a 50% shareholding alongside four veterinary founding shareholders, including CEO Dr Craig Challen. At the time AAH was the second largest companion animal veterinary group in Australia and the largest in WA and SA where it operated 14 veterinary hospitals across Perth and Adelaide under the Vetwest and Adelaide Animal Hospital brands. The investment was the result of a proprietary approach to the founders with an investment thesis built on the opportunity to create a leading veterinary services platform in what was a highly fragmented market. The Australian veterinary sector included thousands of independent clinics, with increasing corporate consolidation supported by changing owner demographics, succession needs and the growing professionalisation of practice management.

Mercury's strategy was to grow AAH through further clinic acquisitions, deepen its geographic footprint in attractive markets and selectively pursue vertical integration across the companion animal services market. In addition, the strategy involved investments in increasing the size and re-branding clinics and opening new ‘greenfield’ sites. The initial focus was Perth and Adelaide, where AAH already had a strong market position and where the combination of Vetwest and Adelaide Animal Hospitals provided a credible platform for consolidation. Mercury also invested in the management infrastructure required to scale the business. This included strengthening finance capability through the appointment of a CFO, recruiting additional senior management capacity and supporting the roll-out of a new practice management system across the clinic network. These systems provided a foundation for KPI benchmarking, clinical performance management and improved decision-making at the clinic level.

During the two years of Mercury’s ownership clinic numbers expanded from 14 to 19 via new site openings and acquisitions. Same-store performance continued to grow, while acquired clinics expanded the group's scale and market relevance. As a result of its growth and success, AAH rapidly became a highly strategic asset and following unsolicited approaches from trade buyers in late 2016 shareholders agreed to sell 100% of AAH to private equity backed vet consolidator Vet Partners. The transaction facilitated Vet Partners entering the West Coast market building upon its strong existing East Coast presence, while also delivering an excellent outcome for all shareholders in the business.