Leiber et al. (2005) discussed that changes in the ruminal ecosystem due to energy shortage or specific secondary plant metabolites may be possible causes for the high C18:3n-3 concentrations in alpine milk. Animals mix plant and biochemical diversity to enhance the nutritive value of the

diet as well as to maintain possible toxic concentrations of plants below critical levels (Provenza and Villalba 2010). Certain plants can also have health benefits for the animals. For example, legumes contain condensed tannins that may cause increased production of milk and wool, improve the lambing percentage and reduce bloating risk as well as intestinal parasites (Min et al. 2003). In addition, Martin et al. (2010) point out that adding tannin-rich legumes to animal

diets may decrease rumen methanogenesis and thus the production Selleckchem Buparlisib of the greenhouse gas methane. As reducing methane production during rumination also means decreasing energy losses by the animals, this is interesting from a production point of view as well. So far, the importance of diverse grasslands in this respect is not completely understood. Thus, despite unclear productivity effects, plant richness may have positive effects on product quality, animal health, nutrient and water retention as well as production stability. The latter may be especially important for sustainable production under changing PF01367338 climatic conditions, but has so far mainly been studied in experimental plots. Livestock management to enhance grassland phytodiversity Extensive grazing has been suggested to be

a good means for enhancing and protecting grassland diversity (Dumont et al. 2007; Hart 2001; Loucougaray et al. 2004; Pykälä 2003; Rook et al. 2004; Diflunisal Scimone et al. 2007; Tallowin et al. 2005). What is the advantage of grazers over mowing? How do the animals influence diversity over time and space? Grazing animals affect the distribution and occurrence of plants in several ways. Besides directly influencing competition between species, they also introduce more heterogeneity into the sward. The main mechanisms in this respect are selective grazing, nutrient redistribution, treading and seed distribution. As the complex actions of biting/defoliation/selection play the most important role in this process (Illius and Hodgson 1996), we will first concentrate on these before discussing the influences of treading and excreta deposition and bringing this together in a discussion of livestock management for biodiversity. Selective grazing Selectively grazing animals preferrably feed on certain pasture areas (horizontal selection) or plant parts (vertical selection) (Arnold and Dudzinski 1978; Elsässer 2000). Given a free choice, they select a mixed diet rather than chosing one fodder species only (Villalba and Provenza 2009). The chosen biomass usually has higher concentrations of nitrogen, phosphorus and energy than avoided material (Wales et al. 1998).