* UN agency criticises Egypt order to cull pigs
* Says flu virus is human, not swine
* Renews calls to change "swine flu" name
By Phil Stewart
ROME, April 29 (Reuters) - Egypt's order on Wednesday to cull all the country's pigs is "a real mistake" and another reason why the world needs to rethink using "swine flu" to describe a virus affecting humans, a U.N. agency official said.
Egypt, where pigs are mainly raised by the country's Christian minority, described the order to slaughter the animals as a precautionary measure in a country hard hit by bird flu. Up to 400,000 pigs could be culled, a cabinet spokesman said.
Joseph Domenech, the chief veterinary officer at the U.N. Food and Agriculture Organisation, told Reuters his staff were trying to reach Egyptian authorities to correct any confusion about a virus that has killed humans but not been found in pigs.
"It's a real mistake. There is no reason to do that. It's not a swine influenza, it's a human influenza," said Domenech, adding the FAO had been trying to reach Egyptian officials but has so far been unsuccessful.
"There is certainly no support from FAO for that decision."
The new H1N1 flu strain -- a mixture of swine, human and avian flu viruses -- has killed up to 159 people in Mexico and a 23-month-old boy in the United States.
But since no pigs have been found with the disease, groups like the FAO and the Paris-based Organisation for Animal Health (OIE) are lobbying for a name change.
"This is one of the results of this strange way of defining the disease as a swine influenza. That's why the FAO and OIE are fighting to get that name changed because it's a totally undue focus on swine," he said.
Egypt, harder hit by the H5N1 bird flu virus than any other country outside Asia, is deeply worried about the effects of another flu virus after extensive damage to its poultry industry and economy.
Egypt's al-Ahram newspaper said owners of culled pigs could receive 1,000 Egyptian pounds ($177) per animal in compensation, although an Egyptian cabinet spokesman said the issue was still under discussion.