Topless Katherine Heigl Cuddles Dog for "I Hate Balls" PSA

Katherine Heigl really hates balls.

Not tennis balls, not yoga balls, but the kind of balls that belong to members of the male persuasion.

In a PSA for the just-launched site IHateBalls.com, the 33-year-old actress jokes that the real reason she's such a proponent for spaying and neutering animals isn't that she's an animal lover, it's that she "hates testicles!" 

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She also shared an exclusive, behind-the-scenes photo with Us Weekly; in the shot, the topless actress wears nothing but panties and a smile as she cuddles an adorable puppy.

"Unfortunately I can't cut the nuts off human men -- yet," she quips in the video. "So I've dedicated my time to the neutering of dogs because that's legal."

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The real reason behind the "New Year's Eve" star's hilarious video? She partnered with Funny or Die on behalf of the Jason Debus Heigl Foundation, named for her late brother who passed away at age 15 in 1986, to raise awareness for and support pet spay-neuter programs.

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A known animal lover, Heigl explains in the clip why she is pro neutering of pets, and encourages a call to action to IHateBalls.com to text, donate and buy "I Hate Balls" gear. The funds raised will benefit the Jason Debus Heigl Foundation, which seeks to eliminate the needless suffering inflicted on animals by human cruelty, indifference and ignorance.

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