A: New York City. Correspondence among practitioners along the East Coast led to a national convention of veterinary surgeons in 1863 in New York City. The first meeting was attended by 40 delegates representing seven states: New York, Massachusetts, New Jersey, Pennsylvania, Maine, Ohio and Delaware.
Elected officers included the French-trained Dr. Alexandre Liautard, who headed the American Veterinary College in New York and was a dominant voice in the profession during this period. Under the direction of Liautard, New York became the unofficial headquarters of the USVMA and the American Veterinary Review was founded to be the voice of the profession. The USVMA was renamed the American Veterinary Medical Association (AVMA) in 1889.
Read more here: AVMA History