Dutch Dairies Reward Grazing

Changing societal drivers and consumer demands require systems that provide desired human foods produced through sustainable production systems. The aim was to show effects of grazing system on milk fatty acid (FA) composition in Dutch farming practice and to analyse current developments in grassland utilization and dairy payments. Milk conjugated linoleic acid (CLA) concentration was a function of hours cows spent at pasture, both at a regional and at a farm scale. Despite beneficial effects of fresh herbage in the dairy production chain on unsaturated FA in milk, the trend in The Netherlands is that cows are more indoors and consume less fresh grass. Action groups have triggered the public debate, mainly from the viewpoint of animal welfare. This has provoked much discussion and raised concern in the public opinion and in politics. Sentiments and marketing rather than scientific evidence dictated the political agenda. In 2011, retailers replaced their private label dairy products with certified products based on milk from farms where cows have access to pasture. The major Dutch dairy company changed its policy in favour of promoting grazing, mainly to preserve the natural image and for providing dairy farmers a societal license to produce. Farmers who graze cows get a premium of €0.50/100 kg milk since 2012

Quality and Vitamins in Forage Herb and Legume Species

Grasslands provide an important part of the feed used by domestic and wild ruminants. Fresh herbage is an important natural source of vitamins in ruminant diets. Concentrations of vitamins in plants depend on factors such as regrowth stage, temperature and day length, N fertilisation and leaf proportion in the harvested herbage. Most studies on vitamin concentrations in forages have been carried out with agronomical important grass species such as perennial ryegrass and legume species such as white clover, but hardly with other grassland forage species. As data of dicotyledonous species grown in a sward are scarce, yield, quality and vitamin contents in a number of herb (hereafter referred to as forb) and legume species were compared to a grass-clover mixture to get an insight into species differences

Effects of Grassland Management on Herbage Lipid Composition and Consequences for Fatty Acids in Milk

Herbage provides bulk feed and is the basis for ruminant nutrition. Herbage lipids, especially C18:3, are a major source of beneficial fatty acids (FA) in milk. These desired FA are unsaturated FA such as CLA (conjugated linoleic acid), especially the isomer rumenic acid, and also vaccenic acid, both trans omega-7 FA (Ellen & Elgersma, 2004). As information on lipids in forages is scarce, effects were studied of N application level and regrowth period on the lipid concentration and FA composition of perennial ryegrass (Lolium perenne L.), the most important forage in temperate climate zones. A linear relation had previously been found between C18:3 intake of cows stall-fed with fresh grass and the amount of omega-7 FA in milk (Elgersma et al., 2003)

The Agrodiversity Experiment: three years of data from a multisite study in intensively managed grasslands

Intensively managed grasslands are globally prominent ecosystems. We investigated whether experimental increases in plant diversity in intensively managed grassland communities can increase their resource use efficiency. This work consisted of a coordinated, continental-scale 33-site experiment. The core design was 30 plots, representing 15 grassland communities at two seeding densities. The 15 communities were comprised of four monocultures (two grasses and two legumes) and 11 four-species mixtures that varied in the relative abundance of the four species at sowing. There were 1028 plots in the core experiment, with another 572 plots sown for additional treatments. Sites agreed a protocol and employed the same experimental methods with certain plot management factors, such as seeding rates and number of cuts, determined by local practice. The four species used at a site depended on geographical location, but the species were chosen according to four functional traits: a fast-establishing grass, a slow-establishing persistent grass, a fast-establishing legume, and a slow-establishing persistent legume. As the objective was to maximize yield for intensive grassland production, the species chosen were all high-yielding agronomic species. The data set contains species-specific biomass measurements (yield per species and of weeds) for all harvests for up to four years at 33 sites. Samples of harvested vegetation were also analyzed for forage quality at 26 sites. Analyses showed that the yield of the mixtures exceeded that of the average monoculture in >97% of comparisons. Mixture biomass also exceeded that of the best monoculture (transgressive overyielding) at about 60% of sites. There was also a positive relationship between the diversity of the communities and aboveground biomass that was consistent across sites and persisted for three years. Weed invasion in mixtures was very much less than that in monocultures. These data should be of interest to ecologists studying relationships between diversity and ecosystem function and to agronomists interested in sustainable intensification. The large spatial scale of the sites provides opportunity for analyses across spatial (and temporal) scales. The database can also complement existing databases and meta-analyses on biodiversity–ecosystem function relationships in natural communities by focusing on those same relationships within intensively managed agricultural grasslands

Weed suppression greatly increased by plant diversity in intensively managed grasslands: A continental-scale experiment

Publisher's version (útgefin grein)Grassland diversity can support sustainable intensification of grassland production through increased yields, reduced inputs and limited weed invasion. We report the effects of diversity on weed suppression from 3 years of a 31-site continental-scale field experiment. At each site, 15 grassland communities comprising four monocultures and 11 four-species mixtures based on a wide range of species' proportions were sown at two densities and managed by cutting. Forage species were selected according to two crossed functional traits, “method of nitrogen acquisition” and “pattern of temporal development”. Across sites, years and sown densities, annual weed biomass in mixtures and monocultures was 0.5 and 2.0 t DM ha−1 (7% and 33% of total biomass respectively). Over 95% of mixtures had weed biomass lower than the average of monocultures, and in two-thirds of cases, lower than in the most suppressive monoculture (transgressive suppression). Suppression was significantly transgressive for 58% of site-years. Transgressive suppression by mixtures was maintained across years, independent of site productivity. Based on models, average weed biomass in mixture over the whole experiment was 52% less (95% confidence interval: 30%–75%) than in the most suppressive monoculture. Transgressive suppression of weed biomass was significant at each year across all mixtures and for each mixture. Weed biomass was consistently low across all mixtures and years and was in some cases significantly but not largely different from that in the equiproportional mixture. The average variability (standard deviation) of annual weed biomass within a site was much lower for mixtures (0.42) than for monocultures (1.77). Synthesis and applications. Weed invasion can be diminished through a combination of forage species selected for complementarity and persistence traits in systems designed to reduce reliance on fertiliser nitrogen. In this study, effects of diversity on weed suppression were consistently strong across mixtures varying widely in species' proportions and over time. The level of weed biomass did not vary greatly across mixtures varying widely in proportions of sown species. These diversity benefits in intensively managed grasslands are relevant for the sustainable intensification of agriculture and, importantly, are achievable through practical farm-scale actions.We thank the many colleagues who have assisted this work. We thank M. Coll for her early contribution. Co-ordination of this project was supported by the EU Commission through COST Action 852 ‘Quality legume-based forage systems for contrasting environments’. M.T.S., R.L. and A.R. were supported by the Spanish Ministry of the Economy and Competitiveness through projects CARBOAGROPAS (CGL2006-13555- C03- 01/ BOS) and BIOGEI (CGL2013-49142- C2- 1- R) and the Ministry of the Environment through OPS (209/PC08/3-08.2). L.K. was supported by an award from Science Foundation Ireland (09/RFP/EOB2546). A.L., J.A.F., J.C. and M.S. were partly supported by the EU FP7 project ‘AnimalChange’ under grant agreement no. 266018.Peer Reviewe

Vitamin contents in forage herbs

Summary Grasslands provide an important part of the feed used by domestic and wild ruminants. Fresh forages are an important natural source of vitamins in ruminant diets. Most studies in forages have been carried out with perennial ryegrass and legume species such as white clover. As yield and quality data of broad-leaf grassland species are scarce, the aim of this study was to obtain novel information on vitamins in a number of herb species compared to a grass-clover mixture and to get insight into species differences and seasonal patterns across the various harvests and years. Seven herb species and a perennial ryegrasswhite clover mixture were investigated in a cutting trial with four harvests (May-Oct) during 2009 and 2010. Vitamin concentrations were highest in October. The α-tocopherol concentrations were lowest in lucerne and yellow sweet clover, and highest in salad burnet and plantain. The β-carotene concentrations were lowest in lucerne, salad burnet and yellow sweet clover and highest in caraway, birdsfoot trefoil and plantain. As various herbs outperformed the grass-clover mixture regarding vitamin concentrations, these might provide added benefits in farming practice beyond higher biodiversity per se

Editorial: Sustainability of grasslands and grass‐based ruminant production – Topics from the 28th General Meeting of the European Grassland Federation

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