Washington estimates for one of the most important numbers in world farming – the size of the Chinese hog herd – may be way too low, US officials in Beijing said, citing improvements in farming practices.

The US Department of Agriculture's Beijing bureau said that the Chinese hog herd entered 2013 more than 8m head larger than suggested by the department's official numbers, which are viewed by agricultural commodity investors as world industry benchmarks.

And the herd will end the year 10m animals larger, at 476.0m head, the bureau said, highlighting the development of the Chinese pig-rearing sector from one dependent largely on backyard output to an industry based around large-scale, and vastly more efficient, commercial enterprises.

Disease risks wane

One impact of this commercialisation was in reducing the spread of diseases which have been a recurrent problem for the sector.

"Swine producers are adopting better practices to prevent and manage disease which limited losses during the peak winter season," the bureau said.

Furthermore, farms, encouraged by a sow subsidy of RMB100 ($15.90) per animal through June 2013, have been increasing numbers of sows, from historical rates of 8-9% of the herd.

"Sources note that the ratio of sows to total swine inventory soared [to] over 10% in 2012 and is expected to reach 11% in 2013."

'Dampen import demand'

The dynamic reflects a further setback to US pork exporters, the major shippers to China, following the hurdle Beijing placed on American supplies by requiring them to be certified free of ractopamine, a growth stimulant.

"Higher domestic production and beginning stocks will likely dampen import demand," the bureau said, slashing by 10% to 730,000 tonnes its forecast for Chinese pork imports this year.

However, the idea of an even larger Chinese pig herd - which already represents more than half the world total - bodes well for foreign grain producers, with the country seen losing its self-sufficiency in corn, and already the biggest importer of soybeans to keep its livestock fed.

Glencore earlier this week highlighted that China would need a pig herd big enough to require an additional 160m tonnes of corn in feed, if per capita pork consumption rates on the mainland came to match those in Hong Kong.

Better for beef

The USDA bureau had better news for beef exporters, in lifting its forecast for Chinese imports of the meat this year from 34,000 tonnes to 90,000 tonnes.

"Imports will likely reach record levels as foreign products are becoming price-competitive to domestic products."

Last year, the average price of imported beef of some $4,150 a tonne was more than 40% lower than the average domestic price, the bureau said.