“The dog was fine,” he said on NBC’s “Today” on Wednesday. “This was a piece of video that was shot during the making of this. Some unknown person at the time. He also spliced, edited and manipulated that to make it look as if the dog was being abused. The dog had been in that water happily, and even afterwards too.”

The German shepherd, a 2-year-old named Hercules, is now “happy and healthy,” Amblin Entertainment, the film’s producer, and Universal Pictures, its distributor, said in a joint statement last week. Hercules was supplied and trained by Birds and Animals Unlimited, a company that frequently works with the film industry.

The American Humane Association, which monitors animals on movie sets and had a representative present during filming, said on Tuesday that the video was “misleading and edited.” Production was stopped after Hercules showed signs of stress, and he was not forced to swim, it said.

Several of the association’s findings were echoed by Gavin Polone, the film’s producer, in a column in The Hollywood Reporter, and by Birds and Animals Unlimited on its website. Mr. Polone said he was not present for the scene but had watched unedited footage of the day’s filming.

Mr. Polone, a vegan who said his will was set up to donate all of his money to animal charities when he dies, said Hercules was eager to swim during rehearsal, at one point “desperate to jump in.” The dog had to be held back by a trainer so he wouldn’t go in too soon, he said.