Farming unions have challenged supermarkets to give sheep farmers a fairer deal in one of the most challenging years in living memory.
Extreme weather, cheap imports suppressing the market and the Schmallenberg virus have piled severe pressure on prices and margins on farms this year.
Lyndon Edwards, chairman of NFU Cymru's livestock board, said: "With lamb prices having been at their lowest for three years the situation for farmers has been made worse by rising production costs due to the extreme weather.
"We've called on retailers to demonstrate genuine commitment to their British suppliers and customers. In 2012 we saw a 22% fall in the farmgate lamb price despite an increase in the price on the supermarket shelves. Now is the time for the supply chain to commit to home produced lamb."
NFU livestock board chairman Charles Sercombe, a sheep farmer in Leicestershire, said: "We want a fair share of the returns to make sure farmers are not in a situation where they are producing lamb for lower than the cost of production.
"The supermarkets have it in their powers to be able to make sure that the dividends they receive from the produce is split more fairly."
In the long term, Mr Sercombe would like to see a better balance of supply and demand that provides farmers with a better return and gets more British produce on supermarket shelves all year round."
With Schmallenberg virus continuing to cause concern as the lambing and calving season progresses, there was considerable interest and discussion at this week's NFU Cymru Livestock Board meeting on progress with regards to the availability of a vaccine against the virus.
Last month, the Veterinary Medicines Directorate (VMD), the agency responsible for regulating and issuing marketing authorisations, took the unprecedented step of providing an update on the progress of an application - that submitted by MSD Animal Health - for its "Bovilis SBV" vaccine.
No date has been given as to when the vaccine will be commercially available. However, the VMD has highlighted that while the vaccine requires rigorous scientific assessment to ensure that the vaccine is safe for the relevant livestock, it is also mindful of the impact the virus is having on individual animals and farmers who have herds and flocks affected by the disease.
Mr Edwards said he hoped that every effort could be made to ensure that a vaccine is available in advance of the periods of peak midge activity this summer so that farmers can have the opportunity to protect their herds and flocks.
As they finish lambing, he urged sheep producers in England, Scotland and Wales to complete a Lamb Crop Survey survey to build up a picture of the Schmallenberg virus.
The survey - provided by Survey Monkey - will stay open until May and will be followed by a calf crop survey in the coming weeks.
Although lamb prices have recovered slightly over the last few weeks, they are still well down on a year ago, with deadweight prices 16% lower than in March 2012.
In the auction markets, standard weight lambs averaged 172.1p/kg across Great Britain in the week to 6 March, a rise of 9.6p/kg despite numbers being 5% higher. Medium weights were 183.1p/kg, up 12.9p on the week. This values a 40kg lamb at 73.24p a head, compared with £81 a head in the same week last year.
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