Much like the Common App, the VMCAS (Veterinary Medical College Application Service) is a centralized application system used by many vet schools. The VMCAS collects biographical data, academic information, animal/veterinary/research experiences, recommendations (eLors), official transcripts, personal essays, and college supplements. The VMCAS now opens in January and students can submit their application from May to mid-September of each application cycle.
Most vet schools use the VMCAS, but some may ask applicants to submit applications in other ways. This link is not updated, but gives an idea of which schools accept the VMCAS. The AAVMC (Association of American Veterinary Medical Colleges) also releases a sample application annually. Updated VMCAS application information can be found here.