Auteur: Elgersma A., Søegaard K. and Jensen S.K.
Jaar van uitgifte: 2015
Fresh herbage is an important natural source of protein, fibre, fatty acids (FA) and vitamins in ruminant diets and it is desirable for farmers that they minimise losses. Thus the concentrations of vitamins and FA in herbages during the growing season as well as their fate after cutting are of interest. A study was conducted in Denmark in which a red clover (Trifolium pratense) – perennial ryegrass (Lolium perenne) sward was mown eight times during the crop growing season. Swaths were subjected to three wilting strategies, and sampled at six time intervals after cutting. Dry matter content and concentrations of α-tocopherol, β-carotene and FA were determined. Fatty acid and α-tocopherol concentrations were highest in October, followed by May, and lowest in summer. Total FA and vitamin concentrations showed a significant overall decline from freshly cut to 29 h-wilted forage. Weather conditions and swath management practices had significant effects on the drying rate of cut forage. The magnitude and rates of decline of concentrations of vitamins and FA during the wilting process were not affected by swath management or herbage drying rates. Choice of harvest date and wilting duration could be used as management tools to optimise concentrations of vitamins and FA in forage.