Farming unions are holding an emergency summit today as they warn dairy and livestock farmers are facing «financial devastation».
Falling lamb and milk prices have led to protests around the country, including one at the weekend that saw cows herded into a supermarket in Stafford.
The National Farmers Union (NFU) is calling on all supermarkets and retailers to be «clear and transparent» in their pricing of milk in order to make sure people know how much farmers are paid.
Some supermarkets are currently paying around 30-33p per litre but others, including Asda, are paying as little as 23p per litre.
The two heifers were led through the aisles of the Asda store by two young boys on Sunday, joined by around 70 protesters.
Footage shows one protester telling shoppers: «The reason we are doing this is the milk is far too cheap.
«If the milk stock is this cheap in six months’ time, there will be no fresh milk in this country. We are packing up. We cannot afford to sell milk at this price.
«This milk should not be cheaper than bottled water.»
The protesters then cleared the supermarket shelves of all the milk, an action called the «Milk Trolley Challenge», which has been happening at stores around the UK.
It sees all the milk on the shelves bought up, then it is either given away or sold for a nominal fee and the money donated to charity.
When police arrived at the Stafford Asda, the protesters became annoyed when an officer touched one of the cows.
«You’re going to upset him,» a man tells the officer.
She responds: «You need to get it out right now.»
Around 200 dairy producers have left the industry since January, according to the NFU.
Farmers say they need to be paid at least 30p a litre of milk to cover their costs.
But they were paid an average 23.66p for a litre of milk in June, according to British dairy organisation AHDB Dairy.
Last week, several UK milk wholesalers cut prices by 0.8p per litre, taking the price paid to some farmers to below 23p.
NFU President Meurig Raymond told Sky News the protesting farmers may have taken things too far.
He said: «Dairy farmers are desperate at the present time and I understand how they have vented their frustration, but it’s so important important that we do not alienate our customers.»
But, he added, more farmers could be put out of business in the next few months.
Mr Raymond said: «The farming industry gets support via the common agricultural policy to take out some of the volatility that we see in market prices, but at the present time even with that support farmers are still losing 8 to 10 pence a litre on their milk that’s being produced.
«The average dairy farmer is producing about 2,500 litres of milk per day. You can easily work out how much the average farmer is losing at the present time and that’s why a lot of dairy farmers are going to make some big decisions in the next few months.»
The NFU’s emergency meeting to discuss the problems facing the industry is taking place in London.
Source: SkyNews