This study aimed at determining the in vitro nutritive value of treated potato vines and evaluating their potential to replace lucerne in ruminant diets. Potato vines were treated as air-dried (H); ensiled without additive (S), with 10% molasses (SM) or with 10% molasses plus 4% urea (SMU); pre-dried and ensiled either with 10% molasses (HSM), or with 10% molasses plus 4% urea (HSMU). Gas production kinetics, and ruminal digestibility and fermentation of the vines were determined in vitro alone or as 20% or 40% of a mixed ration with lucerne. The SMU and HSMU had the highest asymptotic gas production, ruminal digestibility, total volatile fatty acid (TVFA) and microbial protein (MP). Including SMU and HSMU at 40% in the mixed ration resulted also in the highest digestibility, TVFA and MP. These findings indicate the great potential of additive-treated potato vine silages to replace conventional fodder in the diets of ruminants.
