China is the pork powerhouse of the world with over 51 per cent of the world's population of pigs raised there, according to Ron Lane, senior consultant for Genesus in China.

Looking at the size of the breakdown of the inventory for August 2012, breeding stock was around 49.74 million and total on farm inventory was around 464.90 million (as compared to July 2012 breeding stock was around 49.54 million and total on-farm inventory was around 460.75 million). These figures represent increases of 1.8 per cent and 3.1 per cent for the total and sow populations, respectively.

Profit margins continue to show declining returns and many farmers say they are just breaking even.

Since 2001, large specialised and/or commercial farms have been rapidly increasing in market pig production in China, contrasting with the formerly largest production base from the backyard farms. Backyard production has dropped from 74 per cent of total hog production in 2001 down to 37 per cent in 2011, according to Mr Lane, citing a report from Rabobank International.

To promote the development of its agricultural sector, China invested more than six trillion yuan (CNY; US$930 billion) during the decade from 2003 to 2012, the highest in the country's history.

The recently published 11th Revised Edition of the Swine NRC was given much consideration at the Latin American Animal Nutrition Congress (CLANA) in Puerto Vallarta, Mexico.

Dr Lee Southern, Professor Emeritus of the School of Animal Sciences at Louisiana State University in the US presented the committee's work.

"The National Research Council (NRC) is an arm of the National Academy of Sciences. It publishes for any species of animals. It calls itself an unbiased source. It can only use peer-reviewed published literature.

"If there was no published data or change, we didn't make a change. The vitamin information is exactly the same as in 1998. There have been no new published papers on vitamin content in feed ingredients," added Dr Southern.

There are signs that herd liquidation in the US is not as bad as first thought. When corn prices hit more than $8 per bushel back in August, there was plenty of talk about rapid liquidation of the US hog breeding stock.

However, Steve Meyer and Len Steiner now say that individual producers may have reduced some of their numbers but not all sectors of the market have been equally affected.

Sow slaughter for the period 2 September to 20 October shows producers sent 445,000 head to market, about 12,163 head or 2.8 per cent more than a year ago. But sending more sows to slaughter is only one of the ways in which producers can reduce the size of the breeding herd; more gilts destined for the breeding herd may be slaughtered before breeding.

Data from University of Missouri indicates, in fact, that gilt slaughter during the last four weeks was down 1.3 per cent from a year ago. With only a modest increase in sow slaughter and fewer gilts going to slaughter, it is unlikely that come December, the expected reduction in the breeding herd may not have taken place, according to Meyer and Steiner.

It is reported that 85 per cent of Spanish pig farms will comply with the coming EU ban on sow stalls by the deadline on 1 January 2013.