Lady Gaga goes on Oprah after concert canceled

Pop star Lady Gaga performed on "The Oprah Winfrey Show" -- a day after calling off a concert at Purdue University because of an undisclosed illness.

The singer showed no apparent signs of illness as she performed a medley of her hits on the live show Friday. She wore a black outfit studded with spikes and, at one point, swung a gold, spiked ball on a chain into the windshield of a taxi on the stage.

The concert cancellation was announced from the stage Thursday night after opening acts Jason Derulo and Semi Precious Weapons had already performed.

A statement released by the school from Lady Gaga's tour management said she'd suffered a sudden illness and that medical personnel had advised her not to perform.

The concert was rescheduled for Jan. 26.