US meat processor Smithfield Foods is to reduce its US sow herd by 4-5% due to rising grain costs.

The reduction, which will result in 800,000 to 1m fewer market hogs annually, will begin immediately - a large decrease considering Smithfield raises 18 million hogs a year.

"Given the economics for raising hogs today, we cannot continue on the current path, something has to change," said Larry Pope, president and CEO. "Grain costs continue at record levels, with the potential of escalating, given the current US government policy favouring corn for ethanol.

"Today the economics are very challenging and we believe that these increased costs will translate eventually into still higher food costs for the American consumer," Pope added. "In the meantime, Smithfield is taking immediate action to improve the efficiencies of our live production operations."