Compassion in World Farming (CIWF) released film it said it had recently obtained from nine farms in Italy's Po valley exposing the “shocking” conditions endured by exhausted cows wallowing in their own excrement.

The charity is using the footage to launch #notonmypasta, a campaign aimed at pushing producers of the two cheeses to introduce welfare guidelines for their milk suppliers, who manage an estimated 500,000 dairy cattle for a business with annual sales of some five billion euros.

“What our investigators exposed was the misery of life in a factory farm,” said Emma Slawinski, CIWF's Director of Campaigns. “There were extremely underweight, overworked animals being treated like milk machines, suffering just so we can add a topping to our pasta.

“Parmesan and Grana Padano cheeses are marketed as 'high quality' when in fact the reality for the cows couldn't be further from the truth. It's time to put these animals back on the land where they belong.”

A spokesman for the consortium of producers of Parmigiano Reggiano confirmed that production specifications for the upmarket cheese did not cover animal welfare because “it is not something that has an impact, if not marginally, on the quality of the product.”

But he insisted producers cared about welfare standards and said the consortium was in the process of introducing a certification system designed to ensure minimum animal welfare standards are observed.