UC Davis is considered the "best" veterinary school. The reason it is not ranked in many publications is because of it's accredidation status with the AVMA. UC Davis' veterinary school has been on limited accredidation for several years because of deficiencies in "Finances" (CA's University system has had many budget cuts) and "Facilities" (older buildings).
They will soon be fully accredidated though, as there are some very, very nice brand-spanking-new buildings and facilities. Also, their limited accredidation has had NO adverse effects on their graduating students' abilities to take (and pass) national and state licensing exams.