It estimates that 400,000 cattle aged over 30 months - and so destined solely for culling - are being kept on farms around the country.
Farmers say the animals are virtually worthless. But each costs up to pounds 10 to feed each week and is eating into stocks that will be needed to feed the surviving herds between January and March.
The crunch will come at the end of this year, when farmers will have to replenish feed stocks for animals. Most buy in bulk in April, aiming to store enough to last 12 months.
But the unsold and unculled cows have used up more than forecast, which will force farmers to restock early. But in many cases they will not have received payment for the culled animals, as that can take two and a half months to arrive.
Tony Donaldson, an economist at the National Farmers' Union (NFU), said that the problems are being worsened by the collapse in the beef market - caused by the BSE crisis and increasingly strong evidence that BSE-infected food could pass the disease to humans.
"Farmers are losing out both ways, because the price per kilo of cull cows has gone down by 12 per cent compared to last year, while the market value of young cows is down about 20 per cent compared to last year," he said.
Although the Agriculture Minister, Roger Freeman, announced this week that culling will be speeded up, with the aim of clearing the backlog by Christmas, farmers say that the economic damage has already been done. Some have had cattle waiting to be culled since April. The extra cost is pushing many into deepening losses every week, said NFU regional representatives.
Farmers are increasingly gloomy. "Up until three weeks ago I had 90 cows which I didn't want," said Noel Marsh, based near Dorchester, in Dorset, whose dairy herd totals more than 400 cattle. "I got it down to 40, but it's like milking an extra herd." He said that market prices were so low "it almost made me cry." Farmers also expect that the Government's plans to speed up the cull will run into problems next week, when a new registration scheme giving priority to cattle which have been awaiting culling comes into effect. Though it is intended to make it easier for farmers to "queue- jump" older cattle, many expect that administrative delays will mean instead that those without the correct paperwork will have to wait longer - and so keep paying out for cattle which are losing them more money every day.Reuse content