Within conventional silage finishing systems, forage quality is critical to lamb performance and some concentrate feeding is generally required (Fitzgerald, 1987). Rate of finish may also be manipulated by increasing the concentrate component of the diet, particularly in the latter stages of the finishing period. For organic production however, the United Kingdom Register of Organic Food Standards (UKROFS) limit concentrate supplementation to 40% of daily dry matter intake, and a flatter pattern of concentrate allocation is generally required. Where diets containing a high proportion of clover (more likely under an organic or low nitrogen system) are fed, improvements in lamb performance have been shown in grazing animals (Clark, 1988) and following ensiling (Vipond et al, 1992). The aim of this experiment was to assess the potential of high clover silage to finish hill lambs from the organic unit at ADAS Redesdale.

One hundred and forty four approximately six month old Scottish Blackface wether lambs (mean liveweight 30.0 kg, se = 0.24) were housed off silage aftermath and assigned (in pens of twelve) to one of three treatments - grass silage plus 400 g concentrate (GH), high clover silage plus 400 g concentrate (CH) or high clover silage plus 200 g of mineralised barley (CL).