The streets of Manhattan were filled with four-legged New Yorkers Sunday morning jumping with joy and wagging their tails to celebrate an organization's hard work and dedication to protecting animals. 

The ASPCA marked its 150th anniversary on April 10 with the city's first-ever NYC Paws Parade that began at Madison Square Park and stretched down Broadway to Union Square. 

Along with celebrating the ASPCA — which was founded in New York City in 1866 and is now considered to be the first and oldest animal welfare organization in the country — the day also celebrated local groups who have worked hard to protect "some of the city's most vulnerable residents." 

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The parade featured pet celebrities such as Marnie the Dog — who has 1.9 million followers on Instagram — and also included members from the ASPCA, Mayor’s Alliance for NYC’s Animals, Animal Care Centers of NYC, rescue vehicles and more. Marchers also included members of the NYPD Mounted and Canine Units, FDNY mascots Hot Dog and Siren, and many other four-legged New Yorkers.

At the end of the parade at Union Square, the Mayor’s Alliance for NYC’s Animals — in partnership with the Petco Foundation — hosted Adoptapalooza which featured over 300 homeless puppies, kittens, dogs, cats and rabbits — all spayed, neutered and vaccinated.

The Mayor's Alliance and the ASPCA also hosted Adoptapalooza Brooklyn at the House of Vans, which along with featuring more adoptable pets, also included pet celebrity meet-and-greets and a special exhibit showcasing the ASPCA's history.