Egypt began a controversial slaughter of the nation's 250,000 pigs on Saturday, despite the World Health Organisation saying there's no evidence the animals are transmitting swine flu to humans.
One hundred pigs were slaughtered in Alexandria and government workers began transporting an estimated 28,000 pigs in Cairo's Ard el-Liwa neighbourhood to slaughterhouses, the state news agency MENA reported.
The BBC reports farmers clashed with health officials in at least one incident north of Cairo. It says pig-farming and consumption is limited to Egypt's Christian minority, estimated at 10% of the population.
United Nations agencies are still trying to find out if the virus behind the human outbreak is circulating in pigs in Mexico, warning that ongoing swine infection could "worsen" the risk to human health.
Experts have pointed out that the flu cannot be caught by eating pig meat.
Pig herd in Canada infected
Canadian health officials have found swine flu in a pig herd in the province of Alberta but say there is no threat to the food supply.
The Canadian Food Inspection Agency said the herd was quarantined pending more testing, "but that the chances the pigs could transfer the virus to humans was remote."
While further testing is needed "to more fully characterise the virus," the herd "has been placed under quarantine," the agency said.
The agency said the infected pigs apparently caught the virus from a human who traveled recently to Mexico.
It was the first time the agency had reported a case of the virus being transmitted from a human to a pig in Canada.