Feld's father and uncle bought the circus in 1967.
At the end of the 2 1/2 hour show, Ringmaster Johnathan Lee Iverson led the performers, crew and audience in an emotional rendition of "Auld Lang Syne".
A spokesman for the circus says homes have been found for the animals that were owned by Ringling, including the tigers, horses and camels. But the Kill Ringling movement - which includes many groups, among them the Humane Society of the United States, the American Society for the Prevention of Cruelty to Animals and the Performing Animal Welfare Society, as well as celebrities such as "Baywatch" star Pamela Anderson and "Family Guy" creator Seth MacFarlane - was nothing if not dedicated.
The final show of the Ringling Bros. and Barnum & Bailey Circus begins, Sunday, May 21, 2017, in Uniondale, N.Y.
The Ringling Bros. and Barnum & Bailey Circus that has wowed crowds for 146 years with its "Greatest Show on Earth" is taking its final bow.
His parents met at the Ringling circus in 1954.
And so tonight, sometime after 9 p.m., the Greatest Show on Earth will be no more.
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During Sunday's final performance, Alexander Lacey, the circus's big cat trainer, addressed the animal-rights issue directly, pausing from his act to tell the crowd that the circus had bred, raised and cared for 500 lions and tigers - on display Sunday night, he said, were the circus's ninth generation of tigers and 11th generation of lions. "We got to see animals here and the Bronx Zoo. I'm seeing people I haven't seen in years".
Although it eventually was the last of about two dozen American circuses to still travel by train, Ringling continued trying to modernise and surprise.
PETA wants people to go not just vegetarian (cows feel fear) but vegan (eating eggs exploits chickens).
Feld, his voice sometimes shaking, said that in the 50 years that his family had produced the circus, over a quarter-billion people had seen its shows.
In the end, though, Feld executives said they knew the circus couldn't compete with iPhones, the internet, video games and massively branded and carefully marketed characters. Their other productions - Frozen on Ice, Marvel Live, Supercross, Monster Trucks, Disney on Ice - resonate better with younger generations. "This was one of the last nomadic tribes running around the country".
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