According to a statement by the US National Pork Board, the owners of the farm have completely condemned any mistreatment of animals.

The board said the owners will not tolerate the misconduct of any employee involved in the care of animals and they are taking immediate steps to correct the problems at the Bayard, Iowa, farm they bought on 18 August.

Representatives of the owners met with PETA staff members to discuss specific corrective steps on Wednesday morning.

Steve Weaver, National Pork Board President said: "The pork industry condemns the abuse of any animal.

"The National Pork Board and America's pork producers take their ethical responsibility for the proper care of pigs seriously and will not tolerate any mistreatment of animals."

Mr Weaver added: "US pork producers are committed to care for animals in a way that protects their well-being. The industry provides education and training programs - including Pork Quality Assurance Plus® and the Transport Quality Assurance® Program -- to ensure that all persons involved in the care of pigs understand their ethical responsibility and possess the skills necessary to provide good care.

"I also would encourage anyone having knowledge of the possible mistreatment of animals to bring that immediately to the attention of the responsible persons."