Dr. Mehmet Oz, the GOP’s Senate candidate in Pennsylvania, has for nearly two decades been dogged by rumors of past animal abuse. The New Jersey celebrity doctor was once a principal investigator at a Columbia University lab—and, Jezebel reported Monday, conducted research that led to the deaths of 329 dogs. The outlet surveyed 75 of Oz’s studies published between 1989 and 2010, also finding that 31 pigs were killed in two other experiments, while 661 rabbits and rodents were killed in 38 more studies. In May 2004, while Oz was a professor at Columbia’s medical school, the university paid a $2,000 federal fine for alleged violations of the Animal Welfare Act tied to his research. (Earlier this year, The Daily Beast reported that Columbia quietly cut public ties with Oz.) It was not immediately clear how many animals Oz interacted with or may have directly mistreated. But, as whistleblower and veterinarian Catherine Dell’Orto told a Philadelphia outlet last month, “When your name is on the experiment, and the way the experiment is designed inflicts such cruelty to these animals, by design, there’s a problem.