Effect of different levels of wilting on fermentation pattern of lucerne ensiled at two stage of maturity

The study was conducted in the Western Po Valley to evaluate the effect of wiltimg on the fermentation of lucerne ensiled in laboratory silos at two stages of maturity. A first cut of lucerne (cv. Delta) was harvested at late vegetative stage (6 May) and late bud stage (20 May) and ensiled either fresh (179 and 206 g DM kg-1) or wilted. Six wilting levels up to 590 g DM kg-1 at late vegetative and five wilting levels up to 544 g DM kg-1 at late bud stage were considered. The unwilted lucerne in the late vegetative stage had lower dry matter (DM) content, higher buffering capacity, and higher total nitrogen (TN) compared to the late bud stage. The wilting process determined a concentration of the WSC in the plant water from 18 to 113 g l-1 and from 21 to 88 g l-1 in the two stages. The WSC in the DM however decreased by about 6% in both stages. In both stages direct cut and low DM lucerne (< 324 g kg-1) underwent clostridial fermentation. Heavier wilting restricted the fermentation and resulted in well preserved silages. As the conservation quality improved, proteolysis and DM losses decreased, both in late vegetative and in late bud stage.