Cohan added that when kapparot was first established, people were raising chickens in their own backyards and so the animals' suffering would be limited before they were swung about and killed. But today, with the advent of factory farming, the practice is unacceptable.
"The ceremony is a legacy from a different era, a past era," he said. "The chickens were not transported without food and water like they are today. Not that it was ever a good custom, but it's much worse today."
He also is concerned that, in many people's eyes, a fringe practice that most Jews reject could come to be associated with the religion as a whole.
"It's an embarrassment to our religion that the mainstream media ... loves to take images of kapparot ceremonies," he said. "It's unfortunate because it's not mainstream Judaism, and it's unfortunate that there are any Jews using chicken kapparot."