By Brandon Gage Doctor Mehmet Oz, the Republican candidate for the United States Senate in Pennsylvania, conducted research at Columbia University in New York City between 1989 and 2010 that resulted in the grisly deaths of over a thousand animals – including more than 300 dogs – according to dozens of studies that were reviewed by Jezebel. On Monday, the outlet published its findings. Oz, it revealed, “was a ‘principal investigator’ at the Columbia University Institute of Comparative Medicine labs for years and assumed ‘full scientific, administrative, and fiscal responsibility for the conduc…