Open access publications in the SLU publication database

Abstract

The aim of this thesis was to examine the effect of different treatments on the degradation of protein during ensiling, with the aim of minimizing protein degradation. The work is based on three experiments. The first was a study on mechanical treatments during wilting (untouched swath, swath turning, spreading and tedding) and the effects on losses and protein degradation in two crops. In the second study, herbage was ensiled in large round bales, or chopped and ensiled in small-scale silos, and ensiled with or without additives (Inoculant, Kofasil® Ultra formic acid and Proens™). The third experiment tested whether it is beneficial to add the additive, inoculant or Proens™ at mowing rather than baling or chopping. The herbage was then ensiled in small-scale silos or large round bales. The results indicate that increasing dry matter (DM) content of the herbage reduces water soluble N (WSN) content of silage. Tedding the crop made the crop dry faster, but slightly increased the losses of energy and crude protein (CP). Also less WSN was found in silage from herbage with red clover than in pure grass. The second and third study showed that there is no difference in WSN between bales and silos, provided similar DM and the same additive. In the seconds study both chemical and biological additives reduced WSN in silage, though chemical additives, in particular the acids formic acid and Proens™, seemed most effective. In the third study, the bacterial inoculant did not reduce the formation of WSN, but Proens did. There did not appear to be any benefit of applying additives at mowing rather than chopping/baling, though the effect on fermentation, with greater stimulation by the inoculant and greater inhibition by Proens™, seemed greater when the additive was applied at mowing if the herbage was ensiled in bales. The conclusions from the studies are that there is a big difference in WSN between silages. If the goal is to minimise WSN additives and/or high DM content of the silage is recommended. Despite differences in fermentation silage from the same crop, treated with the same additive will contain similar amounts of WSN. Herbage containing red clover will undergo less proteolysis than pure grass herbage.