April 27 was Cornell University’s 150th anniversary. Its charter was signed in Albany in 1865. One of the school’s founders, Ezra Cornell, was a farmer and made veterinary science a priority. This is the story of the career of the first doctor of veterinary medicine to graduate from Cornell.

Daniel Salmon was 18 years old in 1868 when he traveled to Ithaca to go to college. Today the College of Veterinary Medicine at Cornell is a sprawling maze of labs, barns and hospitals. Back then it was much simpler.

“There was just one academic building in the very beginning,” says Donald Smith, former dean of the College of Veterinary Medicine. “Cascadilla Hall was there for students and faculty as a residence and there was very little else except a farm, a working farm.

Salmon’s doctorate from Cornell University was the first awarded in the U.S. The bacteria salmonella was named after him, though his assistant Theobald Smith actually discovered it. And Salmon helped found veterinary colleges in Washington, D.C., and Uruguay. He also developed the first federal meat inspection system in the U.S.

When Salmon’s career reached its peak 30 years after arriving at Cornell, it came right as the profession began to change, too. Smith says at first veterinarians were in the cities and made sure horses could get people where they needed to go.

“And the Civil War was a period when they lost probably a million horses and mules from trauma, but mostly from starvation and disease,” says Smith.

The theory that disease is caused by microscopic germs was developed in the 1870s. Then Louis Pasteur first tested his rabies vaccine in 1885. And as Salmon’s career developed, veterinarians began to move out of the cities to work with farmers, treating diseases.

Today, at a state lab run by Cornell, technicians work on samples from farm animals. They load slides with those samples to see what microbes are in there.