Important legal notice
Contact   |   Search on Europa   
SEARCH ON EU‑AGRINET  Links | Contacts | Disclaimer Printer Friendly
graphic element

Ensiling and grazing of energy-rich grasses with elevated sugar contents for the sustainable production of ruminant livestock

The project aims to provide a sound scientific basis for using novel grasses, bred for high sugar content using conventional breeding methods, in grassland-based agriculture. At certain times of the year, these grasses contain up to 400g sugar per kilo. It is proposed to use these grasses, both grazed and ensiled, on their own and in combination with protein-rich legumes, to improve the efficiency of ruminant production in sustainable livestock systems. The regional focus in northern Europe is the less favoured rural, upland and alpine districts where high-energy forages such as forage maize cannot be grown. Preliminary work has shown that, throughout the year, grasses bred for elevated sugar content contain more sugar than the conventional varieties currently used in ruminant agriculture and that, when fed, significant production responses and environmental benefits are achievable.

This project is concerned with investigating grazing and ensilage strategies for using novel and locally adapted grasses with elevated sugar contents to enhance the supply of protein to the animal and reduce nitrogen pollution to the environment. Grazing studies will investigate the benefits of using high-sugar grasses in dairy and beef production systems, in terms of meat and milk production and reduced environmental N pollution. By investigating the practice of ensiling high-sugar grasses on their own, or in combination with protein-rich legumes, conservation studies will be directed at improving the nutritive value and hygienic quality of silage, further enhancing production efficiency and reducing nitrogen losses to the environment.
Novel grasses bred for their high sugar content are available from the plant-breeding programme of the coordinating organisation (Institute of Grassland and Environmental Research). Locally adapted, high-sugar grass varieties are also available from the partner countries (Germany, Ireland, Norway and Sweden).
The project consists of four work packages.
Work Package 1:
1) to understand the environmental and physiological factors, including N-fertiliser application and growth in ryegrass swards, with or without forage legumes (one or two selected from red clover, white clover or lucerne), which influence sugar production in high-sugar grasses
2) to locate, temporally and spatially, the sites of accumulation of sugar reserves in grasses with elevated sugar contents. This objective will enable climatic influences to be identified and management guidelines to be set to maximise the production of sugar in high-sugar grasses, and optimise strategies for realising their potential when fed to ruminants.
Work Package 2:
To establish techniques for the conservation of grasses with elevated sugar contents that maximise the quantity of sugar in the ensiled crop, and to determine the effect of co-ensilage with forage legumes (one or two, selected from red clover, white clover or lucerne). This objective will result in the development of optimal strategies for conservation of sugar in ensiled herbage and quantify the benefit of ensiling forage legumes with high-sugar grasses.
Work Package 3:
To investigate the hypothesis that elevated levels of sugar in grass will improve protein and energy transactions in the rumen, resulting in improved efficiency of N-use by the rumen microbial population and reduced nitrogen pollution to the environment. The provision of evidence in support of this 'proof of principle' hypothesis is a key scientific deliverable of the project.
Work Package 4:
To determine the production responses and environmental benefits of feeding livestock with grasses of elevated sugar contents, either grazed or conserved, as silage. This objective will quantify the potential production and environmental gains from using high-sugar grasses either alone or in combination with forage legumes (one or two, selected from red clover, white clover or lucerne). It will also consider the economic benefits of using high-sugar grasses in dairy and beef production systems.

Progress to Date
This four-year project is now entering its second year and all of the milestones and deliverables from the first year of the project were achieved. Much of the work of the first year involved the establishment of small plots for agronomic work and lab-based proof of principle studies, and the preparation of larger field areas for farm-scale livestock trials involving grazed and/or ensiled forages. Due to the seasonal nature of the work, many of the results from the first year will not be available until completion of the second periodic report. Some laboratory studies were also conducted during the first year of the project and although data from these studies is included in the first periodic report, the overall significance of the work done so far will not be seen until the second year of the project.

1) It was confirmed that conservation management resulted in higher DM and WSC yields of all grasses than when managed under a simulated grazing regime.
2) The WSC content of several grass species and varieties grown at a total of nine sites across northern Europe was determined. On average, the level of WSC in 2003 was found to be highest in material from the first cut and lowest in that from the fourth cut. The largest differences in WSC content between the high WSC grasses (AberDove and AberDart) and the control variety (Fennema) were in the first and second cuts.


Scientist responsible for the project

Plas Gogerddan
SY23 3EB Aberystwyth
United Kingdom (The) - GB

Phone: +44 1970 823070
Fax: +44 1970 828357


Project ID QLRT-1999-30498
Organisation Institute of Grassland and Environmental Research
Area 5.1.1
Start date 01 August 2001
Duration (months) 48
Total cost 2 758 032 €
Total EC contribution   1 700 000 €
Status Completed
Web address of the project

The partners

  • Institute of Crop and Grassland Science, Federal Agricultural Research Centre, Germany - DE

List by