Chairman Duff Burrell urged them to include 10% beef from older cows to raise demand for the cattle and stabilise cattle prices.
"Farmers can play their part to maintain autumn prices by selling as many cows as possible outside the main culling season and making sure that more of those they cull in autumn are in better market condition," said Burrell.
Processors said there was no problem increasing the use of cow beef. "It's already happening within our supply chain," said John Dracup, procurement director at St Merryn Meats - Tesco's supplier.
"If the mix were to increase it would be down to Tesco. From our perspective, it's ensuring the meat is lean." Asda also said it had a policy of using cow beef in mince and fresh cuts since the ban on Over Thirty Months cattle was lifted in March 2006.