Actor Ryan Gosling is standing up for animal rights by calling on dairy farming officials to put a stop to cruel calf mutilations.

The Notebook hunk, who is dating fellow animal lover Eva Mendes, has written an open letter addressed to Jerry Kozak, the President of the National Milk Producers Federation, urging him to introduce a ban on the painful practise of dehorning.

The message, penned on behalf of leading campaign group People for the Ethical Treatment of Animals (PETA), reads: "I was shocked to learn from my friends at PETA about a practise in the dairy industry called 'dehorning,' which involves painfully burning horn tissue or gouging cows' horns out of their heads, often without the use of any painkillers. I respectfully urge the National Milk Producers Federation to take the lead in stopping this barbaric practise by requiring farmers to phase out dehorning by breeding for polled, or naturally hornless, cattle...

"The American Veterinary Medical Association, the U.S. Department of Agriculture, and third-party animal welfare auditing groups recognize the benefits of polled genetics for the dairy industry, so there is absolutely no reason - and no excuse - for the cruel, unnecessary practise of dehorning to continue. Please do the right thing and take action today."

Gosling isn't the first celebrity to back PETA's latest cause - actor Casey Affleck serves as narrator for a shocking PETA expose film about the cruelty of dehorning.