Not sure but I'll give it a damn good goAs long as you don't have to eat it all on your own.
Deadweight is usually around 50% so I can't see a lamb going to market at 20kg, the slaughter costs are £15 per animal!Nope, definately a lamb, at those sorts of weights your probably talking about a sheep or hogget
That sounds very light to me, the lambs around here don't go to market till they reach about 35 to 40Kg so that's a lot of waste to only make 10kg.
Dead weight is normally around the 20 to 25kg mark.
Maybe your buying half a Lamb?