The U.S. Department of Agriculture attempted to obtain the video through two subpoenas, but Vienna, Va.-based Feld Entertainment would not hand over the footage, a USDA source familiar with the case said Tuesday, speaking on condition of anonymity.
The source said the USDA would pursue other "legal avenues" but did not give specifics.
Under the Animal Welfare Act, the USDA has been investigating the October attack in whichduring a live performance at The Mirage hotel-casino in Las Vegas.
Horn survived but later suffered a stroke that has left him partially paralyzed. The long-running show closed.
USDA spokesman Jim Rogers said Tuesday from Washington D.C., that the probe into the tiger attack remains open. He would not discuss efforts to get the footage or details of the investigation.
The federal act allows the USDA to take action against animal welfare violators and impose fines and suspend or revoke licenses.
Feld Entertainment spokeswoman Shannon Pak declined to comment, citing the ongoing investigation.
The USDA also is investigating the death of a Ringling Bros. circus lion last month. Ringling Bros. is run by Feld Entertainment.
The lion died on a train traveling from Phoenix to California. A lion handler said circus managers ignored his pleas to check on the animal on the long trip through the Mojave Desert, where temperatures can exceed 100 degrees.
Jim Andacht, vice president of circus operations, wrote in an Aug. 14 letter to The Washington Post that "a statement by a former Ringling Bros. employee misrepresented the events before and after the death of our 2-year-old lion, Clyde, including false allegations that our company and employees were withholding information from the U.S. Department of Agriculture."
By Adam Goldman