Australia will investigate claims by an animal rights group that cattle in Vietnam are being slaughtered with sledgehammers but it will not suspend live cattle exports to that country, Prime Minister Tony Abbott said on Wednesday.

Animals Australia said it had "shocking and distressing" footage of animals being slaughtered by repeated blows from a sledgehammer in an abattoir in the north of Vietnam, the second-largest buyer of live cattle from Australia. It said the film was too graphic to be released but it published one photo.

There was no evidence that the animals in the footage were Australian, but animal rights groups demanded that exports of live cattle to Vietnam be suspended, saying that the method of slaughter seen was traditional there.

However, Abbott ruled out any suspension. "We will carefully investigate any allegations. If there's anything in them, we will take appropriate action but the last thing we'll do is close down this trade," he told reporters in Brisbane.

Shipments to Indonesia were halted for a month in 2011 after footage emerged of cruelty to animals there, at huge cost to the industry. Australian Agricultural Company, the country's biggest beef producer, said the suspension cost it about A$50 million ($39.6 million).

Sales of Australian live cattle to Vietnam jumped more than 700 percent between 2008 and 2014, industry body Meat and Livestock Australia said.

According to Australian government forecasts, live cattle exports to Vietnam are expected to be worth A$117 million in the coming season from July 31, second only to sales to Indonesia, which will be worth a forecast A$549 million.

Australia's cattle industry condemned the actions seen in the footage although it said abattoirs that used such methods of slaughter were not approved as slaughterhouses for Australian cattle.

"This latest report captures our worst fears for welfare - that Australian cattle have been illegally removed from our supply chains for quick-buck processing in non-approved slaughterhouses in northern Vietnam," said Alison Penfold, chief executive officer of the Australian Live Exporters Council. ($1 = 1.2620 Australian dollars)