TOKYO, March 25, 2008 (AFP) - Animal rights activists on Tuesday urged Japanese baseball stadiums to give up their usual fare of hot dogs and fried octopus balls and go vegetarian to fight global warming.

Japan's baseball commissioners announced as the season opened last week that the national pastime would take action to reduce greenhouse gas emissions, in particular by speeding up games.

But People for the Ethical Treatment of Animals (PETA) said it would be more effective for concession stands to serve exclusively vegetarian fare.

'By selling only vegetarian foods, your baseball league will become a leader in the fight against global warming,' PETA said in a letter to Nippon Professional Baseball commissioner Yasuchika Negoro.

'Because vegetarians are less prone to serious illnesses like heart disease, diabetes and obesity than meat-eaters, fans will be happier and healthier while cheering on their favourite team,' it said.

A 2006 study by the UN Food and Agriculture Organisation found that the livestock industry contributed more to global warming than all of the world's transportation.

PETA, which is based in the United States, noted that many North American baseball stadiums now offered vegetarian food including burgers made of soy or beans.

The appeal was released hours before the Boston Red Sox, the defending World Series champions, open their regular season against the Oakland Athletics with two games in Tokyo.