Animal Aid has carried out covert filming on 10 pig farms throughout the country, targeting some high profile pig farmers.

The story run in the Independent made a series of allegations about cruelty to animals on British pig farms.

Animal Aid said: "The British pig farming industry makes repeated claims that it has some of the highest welfare standards in the world. Its promotional message – which recently featured in a number of prominent national newspaper advertisements – bolsters this claim by showing healthy-looking pigs on thick straw or out in the fields with plenty of space to roam.

"In March and April 2008, as part of a major investigation, Animal Aid visited 10 English pig farms spanning five counties: Cornwall, Somerset, Lincolnshire, North Yorkshire and East Riding of Yorkshire. Instead of idyllic images of straw-filled pens amidst leafy trees and bathed in sunlight, we found squalor, filth, death and disease."

Animal Aid Head of Campaigns, Kate Fowler-Reeves said: "The pig farming industry has recently launched a media offensive to persuade the public that they should buy British because of the exceptionally high welfare standards on British pig farms. But rarely has there been such a huge disparity between marketing hype and truth."

A BPEX spokesman said: "We are concerned that allegations of cruelty should be made about English pig farms.

"We have obtained the names and addresses of the farms involved from the Animal Aid website. As a matter of routine, independent inspections have been commissioned as provided for under the farm assurance schemes which underpin the Quality Standard Mark.

"British pig farmers are justifiably proud of their welfare standards which are among the highest in Europe.

"We will be contacting Animal Aid to discuss this matter further once the results of the independent inspections are known."