24 th General Meeting of the European Grassland Federation FERMENTATION CHARACTERISTICS, ENERGY VALUE AND CONCENTRATION OF β CAROTENE IN YARROW (Achillea millefolium L.) SILAGE LUKAČ B. 1, KMECL V. 1, VERBIČ J. 1, ŽNIDARŠIČ T. 1, MEGLIČ V. 1, KRAMBERGER B. 2 1 Agricultural institute of Slovenia, Hacquetova ulica 17, 1000 Ljubljana, Slovenia 2 Faculty of agriculture and life sciences, Pivola 10, 2311 Hoče, Slovenia

2/12 Permanent grassland in Slovenia: Covers 58.1 % of utilized agricultural area (Statistical Office RS, 2008). Contains an considerable share of forbs with variable feeding values. Average NEL value of silages 5.9 MJ NEL. There are only few reliable data about silage quality, energy value and β carotene concentration of forbs in literature (Isselstein, Weiβbach…). The following results are from preliminary experiment of larger project, where we study different typs of grass-forbs silage mixtures. Introduction

Yarrow - Achillea millefolium L. The aim of our work was to determine: - β carotene concentration - nutritive value - fermentation characteristic of silage 3/12 A flowering plant. In the past grass leys and permanent pastures contained yarrow. Leaves are rich in minerals - prevention of minerals deficincies in ruminants. Persistent plant in strong competitor with desirable plants on grassland. Poor plant species, regarding WSC concentration fam. Asteraceae More data are needed to draw firm conclusions about fermentation characteristics at different dry matter levels and enviromental conditions.

Summer cut on a natural meadow near the village Murski Črnci (46°37' N; 16°06' E, 190 m a.s.l. in eastern Slovenia). Material and methods Ensiling of the unwilted (UW) and wilted (W) (8 hours) yarrow at the flowering stage in small-scale (1L) laboratory silos. 4/12 Material has been cutt at 1.5 cm lenght.

In vitro gas production technique ß carotene concentration was determined by liquid chromatography (EN ). Chemical analyses 5/12 Liquid chromatography Fermentation quality of silages was assesed by following parameters: pH Ammonia nitrogen Volatile fatty acids Lactic acid. NEL and ME were assessed on the basis of the in vitro gas production technicque and chemical composition using regression equations according to Menke and Steingass (1987). Acids were analysed by gas cromatography.

Characteristics of ensiling material 6/12 In both samples dry matter content were above 200 g kg -1 Wilted material contained almost double amount of dry matter as unwilted material. After 8 hours of wilting beta carotene was reduced for 18%. β carotene concentration is similar to values of Lolium multiflorum L. found in literature, or even higher from Dactylis glomerata L.

Characteristics of ensiling material 7/12 NEL and ME were low - most likely the main reason is maturity of ensiling material. At vegetativ stage yarrow can reach values even above 6 MJ NEL kg -1 DM. (our unpublish data). UW yarrow was relatively poor on WSC. After 8 hours of wilting WSC content increased above 100 g kg -1 DM. CP were about 140 g kg -1 DM.

8/12 Fermentation quality of silages Without signs of detioration. Pleasant aromatic smell of yarrow ant its essential oils in both silages. In wilted silages concentration of Ammonia nitrogen were 3.6 times lower.

Concentration of acids in silages 9/12 Concentration of acids was lower in W than UW silages. Direct cut grass silages usually contain g lactic acid kg -1 DM. Absence of butyric acid in W silage and very low value in UW silage. pH of silages was low enough to prevent growth of Clostridia. According these parameter W silage is considered better.

Nutritive and energy value of silages 10/12 Both silages had similarly low NEL, about 4.6 MJ NEL kg -1 DM. High DM content and lower activity of lactic acid bacteria are reasons for higher WSC concentration in wilted silage. It can be speculated that relatively high WSC concentrations were due to the action of plant hemicellulases during the ensiling process.

Nutritive and energy value of silages 11/12 β carotene concentration in silages (mg kg -1 DM) W silage had 30% lower β carotene concentration than UW silage. The results are in agreement with those obtained on ensiling material. β carotene losses in silages are higher than in ensiling material. Probably is the reason relativly high pH value of wilted silages. Carotenoids losses are higher for legumes than for grasses, when pH is high.

Conclusions Both silages have favorable fermentation. Silage from wilted material contained more WSC, less acetic acid and ammonia nitrogen. Therefore, wilted silage is considered better than unwilted silage. In terms of β carotene preservation ensiling of unwilted material is much better. Silage from unwilted yarrow contained almost 30% more β-carotene then wilted silage. Yarrow silages were characterised by relatively low levels of NEL and ME. The problem of low energy value could possibly be solved by earlier cut of meadows containing considerable proportions of yarrow. Moreover, base on these results and relatively low percetage of yarrow in the sward we are not expecting major impact an silage qulity from permenent grassland. 12/12

Thank you for your attention