Reuters reports that the surge comes after huge investments in rebuilding China's hog herd since the deadly African swine fever disease ravaged farms in 2018 and 2019.

China's pig herd increased to 415.95 million head at the end of March, a 29.5% rise on the year, and up from 406.5 million at the end of December, the National Bureau of Statistics said.

"The fundamental thing is there's more pigs in the herd," said Pan Chenjun, senior analyst at Rabobank.

A severe wave of disease over the winter added to pork production as many farms wary of the rising risk of infection sent pigs to slaughter early.

Average weights of pigs slaughtered were lower than a year ago, said Pan, indicating liquidation by farmers, and a key reason for the increase in output.

Large producers including New Hope Liuhe, Jiangxi Zhengbang and Tech-bank Food Co Ltd have said they culled inefficient sows during the quarter, which amounted to at least several hundred thousand pigs, swelling meat production.

Pork prices have plunged more than 40% since the start of the year, an indication of the large slaughter volume, but they began to recover this week.

That suggests supply is likely not yet back to normal, said Darin Friedrichs, Senior Asia Commodity Analyst at StoneX Group.

"In the past two weeks live hog prices have fallen 15% and rebounded 15%. That doesn't give the impression of an orderly return of supply," he said.

Output in the quarter reached the highest level since the first quarter of 2019 when China produced 14.6 million tonnes of pork, Reuters calculations showed. It was slightly higher than the 13 million tonnes in the fourth quarter of 2020.

China's pork imports for the first three months of 2021 reached 2.63 million tonnes, up 20.8% versus the same period of last year, customs data showed on Tuesday 13 April.

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